<?xml version="1.0" encoding="US-ASCII"?>
<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedBalanceSheets" xlink:href="smg-20191228.xsd#CondensedConsolidatedBalanceSheets" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:href="smg-20191228.xsd#CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedStatementsOfCashFlows" xlink:href="smg-20191228.xsd#CondensedConsolidatedStatementsOfCashFlows" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:href="smg-20191228.xsd#CondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedStatementsOfComprehensiveIncomeLossParenthetical" xlink:href="smg-20191228.xsd#CondensedConsolidatedStatementsOfComprehensiveIncomeLossParenthetical" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CondensedConsolidatedStatementsOfOperations" xlink:href="smg-20191228.xsd#CondensedConsolidatedStatementsOfOperations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/Contingencies" xlink:href="smg-20191228.xsd#Contingencies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ContingenciesDetails" xlink:href="smg-20191228.xsd#ContingenciesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/CoverPage" xlink:href="smg-20191228.xsd#CoverPage" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/Debt" xlink:href="smg-20191228.xsd#Debt" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtComponentsOfLongTermDebtDetails" xlink:href="smg-20191228.xsd#DebtComponentsOfLongTermDebtDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtCreditFacilitiesDetails" xlink:href="smg-20191228.xsd#DebtCreditFacilitiesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtInterestRateSwapAgreementsDetails" xlink:href="smg-20191228.xsd#DebtInterestRateSwapAgreementsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtReceivablesFacilityDetails" xlink:href="smg-20191228.xsd#DebtReceivablesFacilityDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtSeniorNotes4500Details" xlink:href="smg-20191228.xsd#DebtSeniorNotes4500Details" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtSeniorNotes5250Details" xlink:href="smg-20191228.xsd#DebtSeniorNotes5250Details" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtSeniorNotes6000Details" xlink:href="smg-20191228.xsd#DebtSeniorNotes6000Details" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtTables" xlink:href="smg-20191228.xsd#DebtTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DebtWeightedAverageInterestRateDetails" xlink:href="smg-20191228.xsd#DebtWeightedAverageInterestRateDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivities" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivities" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesAdditionalInformationDetails" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivitiesAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesEffectOfDerivativeInstrumentsOnAociAndStatementsOfOperationsDetails" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivitiesEffectOfDerivativeInstrumentsOnAociAndStatementsOfOperationsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesFairValuesOfDerivativeInstrumentsDetails" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivitiesFairValuesOfDerivativeInstrumentsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesOutstandingCommodityContractsDetails" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivitiesOutstandingCommodityContractsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesTables" xlink:href="smg-20191228.xsd#DerivativeInstrumentsAndHedgingActivitiesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DiscontinuedOperations" xlink:href="smg-20191228.xsd#DiscontinuedOperations" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DiscontinuedOperationsAdditionalInformationDetails" xlink:href="smg-20191228.xsd#DiscontinuedOperationsAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DiscontinuedOperationsSummaryOfIncomeFromDiscontinuedOperationsDetails" xlink:href="smg-20191228.xsd#DiscontinuedOperationsSummaryOfIncomeFromDiscontinuedOperationsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/DiscontinuedOperationsTables" xlink:href="smg-20191228.xsd#DiscontinuedOperationsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/Equity" xlink:href="smg-20191228.xsd#Equity" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/EquityAdditionalInformationDetails" xlink:href="smg-20191228.xsd#EquityAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/EquityShareBasedAwardsDetails" xlink:href="smg-20191228.xsd#EquityShareBasedAwardsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/EquitySummaryOfChangesInEquityDetails" xlink:href="smg-20191228.xsd#EquitySummaryOfChangesInEquityDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/EquityTables" xlink:href="smg-20191228.xsd#EquityTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/EquityTotalShareBasedCompensationDetails" xlink:href="smg-20191228.xsd#EquityTotalShareBasedCompensationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FairValueMeasurements" xlink:href="smg-20191228.xsd#FairValueMeasurements" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FairValueMeasurementsDetails" xlink:href="smg-20191228.xsd#FairValueMeasurementsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FairValueMeasurementsTables" xlink:href="smg-20191228.xsd#FairValueMeasurementsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantors" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantors" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsAdditionalInformationDetails" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsBalanceSheetDetails" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsBalanceSheetDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsCashFlowsDetails" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsCashFlowsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsComprehensiveIncomeDetails" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsComprehensiveIncomeDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsStatementOfOperationsDetails" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsStatementOfOperationsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsTables" xlink:href="smg-20191228.xsd#FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ImpairmentRestructuringAndOther" xlink:href="smg-20191228.xsd#ImpairmentRestructuringAndOther" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ImpairmentRestructuringAndOtherActivityRelatedToLiabilitiesAssociatedWithRestructuringDetails" xlink:href="smg-20191228.xsd#ImpairmentRestructuringAndOtherActivityRelatedToLiabilitiesAssociatedWithRestructuringDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ImpairmentRestructuringAndOtherAdditionalInformationDetails" xlink:href="smg-20191228.xsd#ImpairmentRestructuringAndOtherAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ImpairmentRestructuringAndOtherImpairmentRestructuringAndOtherChargesDetails" xlink:href="smg-20191228.xsd#ImpairmentRestructuringAndOtherImpairmentRestructuringAndOtherChargesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/ImpairmentRestructuringAndOtherTables" xlink:href="smg-20191228.xsd#ImpairmentRestructuringAndOtherTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/IncomeTaxes" xlink:href="smg-20191228.xsd#IncomeTaxes" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/IncomeTaxesDetails" xlink:href="smg-20191228.xsd#IncomeTaxesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/Inventories" xlink:href="smg-20191228.xsd#Inventories" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/InventoriesDetails" xlink:href="smg-20191228.xsd#InventoriesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/InventoriesTables" xlink:href="smg-20191228.xsd#InventoriesTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/InvestmentInUnconsolidatedAffiliates" xlink:href="smg-20191228.xsd#InvestmentInUnconsolidatedAffiliates" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/InvestmentInUnconsolidatedAffiliatesDetails" xlink:href="smg-20191228.xsd#InvestmentInUnconsolidatedAffiliatesDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsComponentsOfLeaseCostScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsComponentsOfLeaseCostScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsFutureMinimumAnnualOperatingAndCapitalLeasePaymentsRequiredBeforeAdoptionOfAsu842ScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsFutureMinimumAnnualOperatingAndCapitalLeasePaymentsRequiredBeforeAdoptionOfAsu842ScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsLeasesAndOtherCommitments" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsLeasesAndOtherCommitments" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsMaturitiesOfLeaseLiabilitiesByFiscalYearScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsMaturitiesOfLeaseLiabilitiesByFiscalYearScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsSupplementalBalanceSheetInformationScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsSupplementalBalanceSheetInformationScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsSupplementalCashFlowInformationAndNonCashActivityScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsSupplementalCashFlowInformationAndNonCashActivityScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsTables" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/LeasesAndOtherCommitmentsWeightedAverageRemainingLeaseTermAndDiscountRateScheduleDetails" xlink:href="smg-20191228.xsd#LeasesAndOtherCommitmentsWeightedAverageRemainingLeaseTermAndDiscountRateScheduleDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/MarketingAgreement" xlink:href="smg-20191228.xsd#MarketingAgreement" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/MarketingAgreementAdditionalInformationDetails" xlink:href="smg-20191228.xsd#MarketingAgreementAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/MarketingAgreementNetCommissionEarnedUnderMarketingAgreementDetails" xlink:href="smg-20191228.xsd#MarketingAgreementNetCommissionEarnedUnderMarketingAgreementDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/MarketingAgreementTables" xlink:href="smg-20191228.xsd#MarketingAgreementTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SegmentInformation" xlink:href="smg-20191228.xsd#SegmentInformation" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SegmentInformationNetSalesByGeographicAreaDetails" xlink:href="smg-20191228.xsd#SegmentInformationNetSalesByGeographicAreaDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SegmentInformationNetSalesByProductCategoryDetails" xlink:href="smg-20191228.xsd#SegmentInformationNetSalesByProductCategoryDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SegmentInformationNetSalesProfitLossAndTotalAssetsBySegmentDetails" xlink:href="smg-20191228.xsd#SegmentInformationNetSalesProfitLossAndTotalAssetsBySegmentDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SegmentInformationTables" xlink:href="smg-20191228.xsd#SegmentInformationTables" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SummaryOfSignificantAccountingPolicies" xlink:href="smg-20191228.xsd#SummaryOfSignificantAccountingPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesAdditionalInformationDetails" xlink:href="smg-20191228.xsd#SummaryOfSignificantAccountingPoliciesAdditionalInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:href="smg-20191228.xsd#SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesSupplementalCashFlowInformationDetails" xlink:href="smg-20191228.xsd#SummaryOfSignificantAccountingPoliciesSupplementalCashFlowInformationDetails" xlink:type="simple" />
  <link:roleRef roleURI="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:href="smg-20191228.xsd#SummaryOfSignificantAccountingPoliciesTables" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member" xlink:type="simple" />
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension" xlink:type="simple" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedBalanceSheets" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedBalanceSheetsParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedStatementsOfCashFlows" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedStatementsOfComprehensiveIncomeLoss" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedStatementsOfComprehensiveIncomeLossParenthetical" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/CondensedConsolidatedStatementsOfOperations" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/Contingencies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/ContingenciesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingenciesLineItems" xlink:label="loc_us-gaap_LossContingenciesLineItems_BE7D9C94FA8D5A194F460C7E6FB91334" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingenciesTable" xlink:label="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LossContingenciesLineItems_BE7D9C94FA8D5A194F460C7E6FB91334" xlink:to="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingenciesByNatureOfContingencyAxis" xlink:label="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_E862A12B7B563CC7DFFD0C7EA8E0907F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:to="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_E862A12B7B563CC7DFFD0C7EA8E0907F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_02CE4223E43BAC08AA510C7EA9D4CC56_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_E862A12B7B563CC7DFFD0C7EA8E0907F" xlink:to="loc_us-gaap_LossContingencyNatureDomain_02CE4223E43BAC08AA510C7EA9D4CC56_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingencyNatureDomain" xlink:label="loc_us-gaap_LossContingencyNatureDomain_02CE4223E43BAC08AA510C7EA9D4CC56" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LossContingenciesByNatureOfContingencyAxis_E862A12B7B563CC7DFFD0C7EA8E0907F" xlink:to="loc_us-gaap_LossContingencyNatureDomain_02CE4223E43BAC08AA510C7EA9D4CC56" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_StatementScenarioAxis" xlink:label="loc_srt_StatementScenarioAxis_C992CD6CC382E514E2B40C7CC366F3C5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:to="loc_srt_StatementScenarioAxis_C992CD6CC382E514E2B40C7CC366F3C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="loc_srt_ScenarioUnspecifiedDomain_511C99473084FC342F530C7CC366676A_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_C992CD6CC382E514E2B40C7CC366F3C5" xlink:to="loc_srt_ScenarioUnspecifiedDomain_511C99473084FC342F530C7CC366676A_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="loc_srt_ScenarioUnspecifiedDomain_511C99473084FC342F530C7CC366676A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_C992CD6CC382E514E2B40C7CC366F3C5" xlink:to="loc_srt_ScenarioUnspecifiedDomain_511C99473084FC342F530C7CC366676A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioForecastMember" xlink:label="loc_srt_ScenarioForecastMember_A238EC1382AFD63944300C7CC366C6C5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_511C99473084FC342F530C7CC366676A" xlink:to="loc_srt_ScenarioForecastMember_A238EC1382AFD63944300C7CC366C6C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseAxis" xlink:label="loc_srt_LitigationCaseAxis_A89CF1CB04C6EEF0B49C0C7CC3666A78" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:to="loc_srt_LitigationCaseAxis_A89CF1CB04C6EEF0B49C0C7CC3666A78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseTypeDomain" xlink:label="loc_srt_LitigationCaseTypeDomain_127D0669963D856263170C7CC366EDC0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_A89CF1CB04C6EEF0B49C0C7CC3666A78" xlink:to="loc_srt_LitigationCaseTypeDomain_127D0669963D856263170C7CC366EDC0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseTypeDomain" xlink:label="loc_srt_LitigationCaseTypeDomain_127D0669963D856263170C7CC366EDC0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_A89CF1CB04C6EEF0B49C0C7CC3666A78" xlink:to="loc_srt_LitigationCaseTypeDomain_127D0669963D856263170C7CC366EDC0" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InReScottsEZSeedLitigationMember" xlink:label="loc_smg_InReScottsEZSeedLitigationMember_E9EAB65DB44370CF9F050C7CC367702D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_127D0669963D856263170C7CC366EDC0" xlink:to="loc_smg_InReScottsEZSeedLitigationMember_E9EAB65DB44370CF9F050C7CC367702D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F0EFE7AE987365E4F4540C7CC367071C" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LossContingenciesTable_95BD1A6F2BC0B880C6F90C7CC3651268" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F0EFE7AE987365E4F4540C7CC367071C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_444EBA7D5F9432BAFE3E0C7CC3678B36_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F0EFE7AE987365E4F4540C7CC367071C" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_444EBA7D5F9432BAFE3E0C7CC3678B36_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_444EBA7D5F9432BAFE3E0C7CC3678B36" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_F0EFE7AE987365E4F4540C7CC367071C" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_444EBA7D5F9432BAFE3E0C7CC3678B36" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_WildBirdFoodMember" xlink:label="loc_smg_WildBirdFoodMember_A8849C8E94EF664E8C790C7CC3682CB5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_444EBA7D5F9432BAFE3E0C7CC3678B36" xlink:to="loc_smg_WildBirdFoodMember_A8849C8E94EF664E8C790C7CC3682CB5" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/CoverPage" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/Debt" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtComponentsOfLongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_DD898E97AAA5873D828C169DE724B444" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_DebtInstrumentTable_DD898E97AAA5873D828C169DE724B444" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_BAF867F312DFCB1A6456169DE724E0B7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_DD898E97AAA5873D828C169DE724B444" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_BAF867F312DFCB1A6456169DE724E0B7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_BAF867F312DFCB1A6456169DE724E0B7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_BAF867F312DFCB1A6456169DE724E0B7" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember_77276A0E9C9F6538F428169DE7256007" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_us-gaap_LineOfCreditMember_77276A0E9C9F6538F428169DE7256007" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_698C1BF33732142DAABD169DE725DCAA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_us-gaap_SeniorNotesMember_698C1BF33732142DAABD169DE725DCAA" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MasterAccountsReceivablePurchaseAgreementMember" xlink:label="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_02D1DAB12456F22500FC169DE725EC33" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_02D1DAB12456F22500FC169DE725EC33" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CapitalLeaseObligationsMember" xlink:label="loc_us-gaap_CapitalLeaseObligationsMember_7D51B531AE0DC5C31627169DE7257C18" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_us-gaap_CapitalLeaseObligationsMember_7D51B531AE0DC5C31627169DE7257C18" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DebtOtherMember" xlink:label="loc_smg_DebtOtherMember_7F7206755B1A35741ED0169DE726FDC4" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_smg_DebtOtherMember_7F7206755B1A35741ED0169DE726FDC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtMember" xlink:label="loc_us-gaap_LongTermDebtMember_DC4B3B26700D82E97131169DE7265C80" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_DACA8705F756D6C8997A169DE725EDF5" xlink:to="loc_us-gaap_LongTermDebtMember_DC4B3B26700D82E97131169DE7265C80" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_EC5ACECD5C01441CE09D169DE72616C1" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_DD898E97AAA5873D828C169DE724B444" xlink:to="loc_us-gaap_CreditFacilityAxis_EC5ACECD5C01441CE09D169DE72616C1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_EC5ACECD5C01441CE09D169DE72616C1" xlink:to="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_EC5ACECD5C01441CE09D169DE72616C1" xlink:to="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_70EB8845169C2FF81021169DE726DAAD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_70EB8845169C2FF81021169DE726DAAD" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TermLoanMember" xlink:label="loc_smg_TermLoanMember_60DECDE773B99C83A39D169DE7279C4F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_9C03389FE9C6D512B1F3169DE726837A" xlink:to="loc_smg_TermLoanMember_60DECDE773B99C83A39D169DE7279C4F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_186F80B9088035DBF2D9169DE7278C48" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_DD898E97AAA5873D828C169DE724B444" xlink:to="loc_us-gaap_DebtInstrumentAxis_186F80B9088035DBF2D9169DE7278C48" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_186F80B9088035DBF2D9169DE7278C48" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_186F80B9088035DBF2D9169DE7278C48" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotesFiveandAQuarterPercentMember" xlink:label="loc_smg_SeniorNotesFiveandAQuarterPercentMember_060AC7430FB34C04CAC1169DE72787E7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9" xlink:to="loc_smg_SeniorNotesFiveandAQuarterPercentMember_060AC7430FB34C04CAC1169DE72787E7" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes4.500Due2029Member" xlink:label="loc_smg_SeniorNotes4.500Due2029Member_1BC3004B5A562F90DEFD169DE728ABF4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9" xlink:to="loc_smg_SeniorNotes4.500Due2029Member_1BC3004B5A562F90DEFD169DE728ABF4" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_1EF792CE1B90A5BB26BB169DE728B89F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_A0EE7A90A7C35C231A48169DE72766C9" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_1EF792CE1B90A5BB26BB169DE728B89F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_895947DD1D3CF00EF967169DE7283867" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_DebtInstrumentTerm_895947DD1D3CF00EF967169DE7283867" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_52C327C0E5D54DE5F8A7169DE729C8A7" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_52C327C0E5D54DE5F8A7169DE729C8A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_3C9AE94690EA5CC3786D169DE7294159" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_3C9AE94690EA5CC3786D169DE7294159" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_D2607828C678EA65F948169DE72938FF" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_LongTermDebtCurrent_D2607828C678EA65F948169DE72938FF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_C098549E4FBD8124FFE7169DE7296A2C" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_C098549E4FBD8124FFE7169DE7296A2C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_1F9A6FD54A0D306C23D8169DE7292A65" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_1F9A6FD54A0D306C23D8169DE7292A65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherShortTermBorrowings" xlink:label="loc_us-gaap_OtherShortTermBorrowings_D60BDFA2C0D0EE5D4276169DE729F613" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_OtherShortTermBorrowings_D60BDFA2C0D0EE5D4276169DE729F613" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue" xlink:label="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_31082E463E8ADCD75180169DE72AD688" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_B42A3CE311FF1470E553169DE7285705" xlink:to="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_31082E463E8ADCD75180169DE72AD688" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtCreditFacilitiesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_StatementScenarioAxis" xlink:label="loc_srt_StatementScenarioAxis_5AD73D5CFBFE624DDF01105D95962C9F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_srt_StatementScenarioAxis_5AD73D5CFBFE624DDF01105D95962C9F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="loc_srt_ScenarioUnspecifiedDomain_552A632B8C838012F582105D959689D2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_5AD73D5CFBFE624DDF01105D95962C9F" xlink:to="loc_srt_ScenarioUnspecifiedDomain_552A632B8C838012F582105D959689D2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="loc_srt_ScenarioUnspecifiedDomain_552A632B8C838012F582105D959689D2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_5AD73D5CFBFE624DDF01105D95962C9F" xlink:to="loc_srt_ScenarioUnspecifiedDomain_552A632B8C838012F582105D959689D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScenarioForecastMember" xlink:label="loc_srt_ScenarioForecastMember_5D3AB95CB88EB2452BD5105D9597D8AD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_552A632B8C838012F582105D959689D2" xlink:to="loc_srt_ScenarioForecastMember_5D3AB95CB88EB2452BD5105D9597D8AD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_FD9B366996094DF9865B105D9597F211" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_FD9B366996094DF9865B105D9597F211" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_C0C8834C450F386800B2105D95970FE5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_FD9B366996094DF9865B105D9597F211" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_C0C8834C450F386800B2105D95970FE5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_C0C8834C450F386800B2105D95970FE5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_FD9B366996094DF9865B105D9597F211" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_C0C8834C450F386800B2105D95970FE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember_A3D6308A035A2A041702105D9597A929" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_C0C8834C450F386800B2105D95970FE5" xlink:to="loc_us-gaap_LineOfCreditMember_A3D6308A035A2A041702105D9597A929" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_EC343B3E39337BCAE72F105D9598923F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_us-gaap_DebtInstrumentAxis_EC343B3E39337BCAE72F105D9598923F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1BAB58FB8F32507E0305105D95987FCD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_EC343B3E39337BCAE72F105D9598923F" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1BAB58FB8F32507E0305105D95987FCD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1BAB58FB8F32507E0305105D95987FCD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_EC343B3E39337BCAE72F105D9598923F" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1BAB58FB8F32507E0305105D95987FCD" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember" xlink:label="loc_smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember_73C48BD6FE059AFC5A80105D959876D7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1BAB58FB8F32507E0305105D95987FCD" xlink:to="loc_smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember_73C48BD6FE059AFC5A80105D959876D7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityAxis" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_08CD2884C9F935EECF3B105D9599FCE5" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_us-gaap_LineOfCreditFacilityAxis_08CD2884C9F935EECF3B105D9599FCE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityLenderDomain" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_08CD2884C9F935EECF3B105D9599FCE5" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityLenderDomain" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_08CD2884C9F935EECF3B105D9599FCE5" xlink:to="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_CB5AB324320451E77FEB105D959ABBFB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_CB5AB324320451E77FEB105D959ABBFB" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SecuredTermLoanMember" xlink:label="loc_smg_SecuredTermLoanMember_E26F87936BB3D6233D55105D959A5E01" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_CB2C2F79DEC979AF4F50105D959964F0" xlink:to="loc_smg_SecuredTermLoanMember_E26F87936BB3D6233D55105D959A5E01" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_5C922DAA1F6251236A3D105D959A9F8C" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_us-gaap_CreditFacilityAxis_5C922DAA1F6251236A3D105D959A9F8C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_5C922DAA1F6251236A3D105D959A9F8C" xlink:to="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_5C922DAA1F6251236A3D105D959A9F8C" xlink:to="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_4AA0B9CCE99EEAA8A9CE105D959A2CF8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_4AA0B9CCE99EEAA8A9CE105D959A2CF8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_44714FC9C4FD8B4F1D2D105D959B8685" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_918689E4C4D3A671EE0E105D959A1B67" xlink:to="loc_us-gaap_LetterOfCreditMember_44714FC9C4FD8B4F1D2D105D959B8685" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_DAF3DF6222AF5BA8203C105D959BC0B2" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_90DA1AD0BF3285AE9CAA105D9596B480" xlink:to="loc_srt_RangeAxis_DAF3DF6222AF5BA8203C105D959BC0B2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_DAF3DF6222AF5BA8203C105D959BC0B2" xlink:to="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_DAF3DF6222AF5BA8203C105D959BC0B2" xlink:to="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_BB6EB0491CBF407DB2F7105D959B3B37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC" xlink:to="loc_srt_MaximumMember_BB6EB0491CBF407DB2F7105D959B3B37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_601FF1588EFD66104EFA105D959C4F83" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_787AF646E8685823372C105D959BFCCC" xlink:to="loc_srt_MinimumMember_601FF1588EFD66104EFA105D959C4F83" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DebtMaturityPeriod" xlink:label="loc_smg_DebtMaturityPeriod_812D6FEAE2FAD33EEBDB1089D1708632" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_smg_DebtMaturityPeriod_812D6FEAE2FAD33EEBDB1089D1708632" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2A7D9014340B21C68534105D959F1A21" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_2A7D9014340B21C68534105D959F1A21" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit_D48640991C8A46CC42EC105D959F13FC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_us-gaap_LineOfCredit_D48640991C8A46CC42EC105D959F13FC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_2341C1A662D3661FA94D105D959F7CF0" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_2341C1A662D3661FA94D105D959F7CF0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtWeightedAverageInterestRate" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_C33C54AC332179D4EB1D105D959F3E02" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_C33C54AC332179D4EB1D105D959F3E02" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LeverageRatio" xlink:label="loc_smg_LeverageRatio_3591A9795D3C426828A6105D959F7031" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_smg_LeverageRatio_3591A9795D3C426828A6105D959F7031" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestCoverageRatio" xlink:label="loc_smg_InterestCoverageRatio_F0F3F5C8FDCBA1E36684105D959F7942" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_smg_InterestCoverageRatio_F0F3F5C8FDCBA1E36684105D959F7942" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LeverageRatioRestrictedPaymentThreshold" xlink:label="loc_smg_LeverageRatioRestrictedPaymentThreshold_99D9D759CBB3590B3E7D105D959F9036" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_smg_LeverageRatioRestrictedPaymentThreshold_99D9D759CBB3590B3E7D105D959F9036" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DebtInstrumentRestrictedPaymentLimitationYearsTwoAndThereafter" xlink:label="loc_smg_DebtInstrumentRestrictedPaymentLimitationYearsTwoAndThereafter_22C29712A43AEC1CFD18105D95A08E5F" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_1AC36B502072BE496E63105D959E1C65" xlink:to="loc_smg_DebtInstrumentRestrictedPaymentLimitationYearsTwoAndThereafter_22C29712A43AEC1CFD18105D95A08E5F" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtInterestRateSwapAgreementsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeLineItems" xlink:label="loc_us-gaap_DerivativeLineItems_EE56363EA793A89C77B9105D958CA227" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeTable" xlink:label="loc_us-gaap_DerivativeTable_B77F7338BCE5658DEDFB105D958980A6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_EE56363EA793A89C77B9105D958CA227" xlink:to="loc_us-gaap_DerivativeTable_B77F7338BCE5658DEDFB105D958980A6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_32221137713A00BA0FDC105D9589A65A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_B77F7338BCE5658DEDFB105D958980A6" xlink:to="loc_us-gaap_HedgingDesignationAxis_32221137713A00BA0FDC105D9589A65A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_FA32885777E647201221105D958904F5_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_32221137713A00BA0FDC105D9589A65A" xlink:to="loc_us-gaap_HedgingDesignationDomain_FA32885777E647201221105D958904F5_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_FA32885777E647201221105D958904F5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_32221137713A00BA0FDC105D9589A65A" xlink:to="loc_us-gaap_HedgingDesignationDomain_FA32885777E647201221105D958904F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DesignatedAsHedgingInstrumentMember" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_C9F6407FD58640F0E7B8105D958AE415" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_FA32885777E647201221105D958904F5" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_C9F6407FD58640F0E7B8105D958AE415" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_0918389EED86A577652F105D958A2F36" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_B77F7338BCE5658DEDFB105D958980A6" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_0918389EED86A577652F105D958A2F36" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_48243E8A3DC90F078A93105D958A7B52_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_0918389EED86A577652F105D958A2F36" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_48243E8A3DC90F078A93105D958A7B52_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_48243E8A3DC90F078A93105D958A7B52" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_0918389EED86A577652F105D958A2F36" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_48243E8A3DC90F078A93105D958A7B52" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_48243E8A3DC90F078A93105D958A7B52" xlink:to="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestRateSwapInstrument1Member" xlink:label="loc_smg_InterestRateSwapInstrument1Member_BCB90BD85C877B61083F105D958BD01D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:to="loc_smg_InterestRateSwapInstrument1Member_BCB90BD85C877B61083F105D958BD01D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestRateSwapInstrument2Member" xlink:label="loc_smg_InterestRateSwapInstrument2Member_069DB7DF66E83A1ECB92105D958BEF3F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:to="loc_smg_InterestRateSwapInstrument2Member_069DB7DF66E83A1ECB92105D958BEF3F" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestRateSwapInstrument3Member" xlink:label="loc_smg_InterestRateSwapInstrument3Member_97A609B12C3B909B91BB105D958BAD39" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:to="loc_smg_InterestRateSwapInstrument3Member_97A609B12C3B909B91BB105D958BAD39" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestRateSwapInstrument4Member" xlink:label="loc_smg_InterestRateSwapInstrument4Member_76CD653991F755930BE6105D958B0AD9" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:to="loc_smg_InterestRateSwapInstrument4Member_76CD653991F755930BE6105D958B0AD9" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InterestRateSwapInstrument5Member" xlink:label="loc_smg_InterestRateSwapInstrument5Member_0C1D2860FF114CAFC950105D958CE47E" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_62C103377E8879516DBA105D958B3D40" xlink:to="loc_smg_InterestRateSwapInstrument5Member_0C1D2860FF114CAFC950105D958CE47E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeNotionalAmount" xlink:label="loc_us-gaap_DerivativeNotionalAmount_91CE089FC5FC2E5E2A62105D958C7407" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_EE56363EA793A89C77B9105D958CA227" xlink:to="loc_us-gaap_DerivativeNotionalAmount_91CE089FC5FC2E5E2A62105D958C7407" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeFixedInterestRate" xlink:label="loc_us-gaap_DerivativeFixedInterestRate_30AC2C6A5C22E076B78A105D958CEB9F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_EE56363EA793A89C77B9105D958CA227" xlink:to="loc_us-gaap_DerivativeFixedInterestRate_30AC2C6A5C22E076B78A105D958CEB9F" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtReceivablesFacilityDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_94847D77BE4AF8A29F211075EE4E8FB2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_DebtInstrumentTable_94847D77BE4AF8A29F211075EE4E8FB2" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaap_FinancialInstrumentAxis_8ED39245792BCA004A2C1075EE9ED898" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_94847D77BE4AF8A29F211075EE4E8FB2" xlink:to="loc_us-gaap_FinancialInstrumentAxis_8ED39245792BCA004A2C1075EE9ED898" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_8ED39245792BCA004A2C1075EE9ED898" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_8ED39245792BCA004A2C1075EE9ED898" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MasterRepurchaseAndFrameworkAgreementsTheAmendmentsMember" xlink:label="loc_smg_MasterRepurchaseAndFrameworkAgreementsTheAmendmentsMember_043150A5A71DAF453C411075EEBCB5B8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83" xlink:to="loc_smg_MasterRepurchaseAndFrameworkAgreementsTheAmendmentsMember_043150A5A71DAF453C411075EEBCB5B8" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ReceivablesFacilityMember" xlink:label="loc_smg_ReceivablesFacilityMember_6D174F1C5EA894E83DE91075EECB5943" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83" xlink:to="loc_smg_ReceivablesFacilityMember_6D174F1C5EA894E83DE91075EECB5943" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MasterAccountsReceivablePurchaseAgreementMember" xlink:label="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_503BBF1D503FD61F60751075EED82C0C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_278B9B721433A35A0C091075EEA23B83" xlink:to="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_503BBF1D503FD61F60751075EED82C0C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NotesReceivableGross" xlink:label="loc_us-gaap_NotesReceivableGross_48219A9F2D5EC691FC091075EE66BA1D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_NotesReceivableGross_48219A9F2D5EC691FC091075EE66BA1D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod_09C25B52CE443C76EA8D1075EE733290" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod_09C25B52CE443C76EA8D1075EE733290" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherShortTermBorrowings" xlink:label="loc_us-gaap_OtherShortTermBorrowings_9B68FA79C1A7A87358091075EE7C6BD0" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_OtherShortTermBorrowings_9B68FA79C1A7A87358091075EE7C6BD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue" xlink:label="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_947F9226916829EDA9791075EE86F06D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_947F9226916829EDA9791075EE86F06D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_F27BC71F69342520648B1075EE92AADD" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_F2553AB851A4709D5C981075EE5654E8" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_F27BC71F69342520648B1075EE92AADD" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtSeniorNotes4500Details" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_42D721D5B3F0E2830BB1107154808890" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_61E223CCB85729D1FB8110715479D340" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_42D721D5B3F0E2830BB1107154808890" xlink:to="loc_us-gaap_DebtInstrumentTable_61E223CCB85729D1FB8110715479D340" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_A184852F137111CAC56B10715479FE8E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_61E223CCB85729D1FB8110715479D340" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_A184852F137111CAC56B10715479FE8E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_6F7139DD7A9A07A45EE81071547A50DD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_A184852F137111CAC56B10715479FE8E" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_6F7139DD7A9A07A45EE81071547A50DD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_6F7139DD7A9A07A45EE81071547A50DD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_A184852F137111CAC56B10715479FE8E" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_6F7139DD7A9A07A45EE81071547A50DD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_53B4758E68508FCB63AC107154B30107" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_6F7139DD7A9A07A45EE81071547A50DD" xlink:to="loc_us-gaap_SeniorNotesMember_53B4758E68508FCB63AC107154B30107" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_868555D08C1EEF7AE2441071547B1083" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_61E223CCB85729D1FB8110715479D340" xlink:to="loc_us-gaap_DebtInstrumentAxis_868555D08C1EEF7AE2441071547B1083" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_868555D08C1EEF7AE2441071547B1083" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_868555D08C1EEF7AE2441071547B1083" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotesFiveandAQuarterPercentMember" xlink:label="loc_smg_SeniorNotesFiveandAQuarterPercentMember_30BF74BB484B3B2B4C0C107154A9BA20" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9" xlink:to="loc_smg_SeniorNotesFiveandAQuarterPercentMember_30BF74BB484B3B2B4C0C107154A9BA20" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes4.500Due2029Member" xlink:label="loc_smg_SeniorNotes4.500Due2029Member_DDDD5021A681E7ED500B107154BD1631" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9" xlink:to="loc_smg_SeniorNotes4.500Due2029Member_DDDD5021A681E7ED500B107154BD1631" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_905423A30B7E48650928107154C72198" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_8F84855BBB74954507211071547B09D9" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_905423A30B7E48650928107154C72198" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4A86C04BA3D0248EDFE21071548FCAC0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_42D721D5B3F0E2830BB1107154808890" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4A86C04BA3D0248EDFE21071548FCAC0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfUnsecuredDebt" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfUnsecuredDebt_EF3091B919282AC2B0821071549A5245" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_42D721D5B3F0E2830BB1107154808890" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfUnsecuredDebt_EF3091B919282AC2B0821071549A5245" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtSeniorNotes5250Details" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_E4506FEE6705790122AF106F80622AA4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_BD04E1A747814E71CF11106F805B30E6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_E4506FEE6705790122AF106F80622AA4" xlink:to="loc_us-gaap_DebtInstrumentTable_BD04E1A747814E71CF11106F805B30E6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_016468086034126ADDE3106F805C8309" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_BD04E1A747814E71CF11106F805B30E6" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_016468086034126ADDE3106F805C8309" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_16547802E54CE2F2773D106F805CBA57_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_016468086034126ADDE3106F805C8309" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_16547802E54CE2F2773D106F805CBA57_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_16547802E54CE2F2773D106F805CBA57" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_016468086034126ADDE3106F805C8309" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_16547802E54CE2F2773D106F805CBA57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_8464368322B6AB87E787106F808D2C8E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_16547802E54CE2F2773D106F805CBA57" xlink:to="loc_us-gaap_SeniorNotesMember_8464368322B6AB87E787106F808D2C8E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_70C02F5F55DF3FEDF4F7106F805CE498" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_BD04E1A747814E71CF11106F805B30E6" xlink:to="loc_us-gaap_DebtInstrumentAxis_70C02F5F55DF3FEDF4F7106F805CE498" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_12C279B22CE352A1145A106F805D7312_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_70C02F5F55DF3FEDF4F7106F805CE498" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_12C279B22CE352A1145A106F805D7312_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_12C279B22CE352A1145A106F805D7312" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_70C02F5F55DF3FEDF4F7106F805CE498" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_12C279B22CE352A1145A106F805D7312" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotesFiveandAQuarterPercentMember" xlink:label="loc_smg_SeniorNotesFiveandAQuarterPercentMember_D6F80A0D71C86C557AA1106F80988556" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_12C279B22CE352A1145A106F805D7312" xlink:to="loc_smg_SeniorNotesFiveandAQuarterPercentMember_D6F80A0D71C86C557AA1106F80988556" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_D8EAF8F0D411302DAF58106F884B74C6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_E4506FEE6705790122AF106F80622AA4" xlink:to="loc_us-gaap_DebtInstrumentTerm_D8EAF8F0D411302DAF58106F884B74C6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_39006E832FD0E6D09248106F807534E6" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_E4506FEE6705790122AF106F80622AA4" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_39006E832FD0E6D09248106F807534E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_9B37BED8DD7A27A0AABD106F80818D87" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_E4506FEE6705790122AF106F80622AA4" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_9B37BED8DD7A27A0AABD106F80818D87" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtSeniorNotes6000Details" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable_F0D76A41E438240C3E161073A45A7817" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_us-gaap_DebtInstrumentTable_F0D76A41E438240C3E161073A45A7817" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_AF58CF420EAD9ABBBD941073A45AF38E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_F0D76A41E438240C3E161073A45A7817" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_AF58CF420EAD9ABBBD941073A45AF38E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_92BC384899F2B217D2EF1073A45B247B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_AF58CF420EAD9ABBBD941073A45AF38E" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_92BC384899F2B217D2EF1073A45B247B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_92BC384899F2B217D2EF1073A45B247B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_AF58CF420EAD9ABBBD941073A45AF38E" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_92BC384899F2B217D2EF1073A45B247B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_42D92C34FD1C0C4E0B0E1073A4BAF23A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_92BC384899F2B217D2EF1073A45B247B" xlink:to="loc_us-gaap_SeniorNotesMember_42D92C34FD1C0C4E0B0E1073A4BAF23A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_6521C44B68B982A76B5C1073A45CE751" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_F0D76A41E438240C3E161073A45A7817" xlink:to="loc_us-gaap_DebtInstrumentAxis_6521C44B68B982A76B5C1073A45CE751" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_035095ED69841CD334DF1073A45C0085_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_6521C44B68B982A76B5C1073A45CE751" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_035095ED69841CD334DF1073A45C0085_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_035095ED69841CD334DF1073A45C0085" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_6521C44B68B982A76B5C1073A45CE751" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_035095ED69841CD334DF1073A45C0085" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_A4C75D7976D5618A65371073A4B0BAC3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_035095ED69841CD334DF1073A45C0085" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_A4C75D7976D5618A65371073A4B0BAC3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_FF60B502D0C36B904F9D1073A46E5519" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_FF60B502D0C36B904F9D1073A46E5519" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfSeniorDebt" xlink:label="loc_us-gaap_RepaymentsOfSeniorDebt_E238B6972EBC8CFAF0D11073A479E2C8" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_us-gaap_RepaymentsOfSeniorDebt_E238B6972EBC8CFAF0D11073A479E2C8" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RepaymentsOfSeniorDebtAccruedAndUnpaidInterest" xlink:label="loc_smg_RepaymentsOfSeniorDebtAccruedAndUnpaidInterest_BBCBB184D7EE73C952791073A48216EC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_smg_RepaymentsOfSeniorDebtAccruedAndUnpaidInterest_BBCBB184D7EE73C952791073A48216EC" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RepaymentsOfSeniorDebtRedemptionPremium" xlink:label="loc_smg_RepaymentsOfSeniorDebtRedemptionPremium_E41D987B2A15C39209131073A48ECAE9" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_smg_RepaymentsOfSeniorDebtRedemptionPremium_E41D987B2A15C39209131073A48ECAE9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet_828F9E58D5241222987E1073A4A2D681" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_us-gaap_DeferredFinanceCostsNet_828F9E58D5241222987E1073A4A2D681" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RepaymentsOfSeniorDebtOutstandingPrincipal" xlink:label="loc_smg_RepaymentsOfSeniorDebtOutstandingPrincipal_C56AF60C46346EF4B9691073A498CABD" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_DFE233EAB8829297DE221073A46153DD" xlink:to="loc_smg_RepaymentsOfSeniorDebtOutstandingPrincipal_C56AF60C46346EF4B9691073A498CABD" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DebtWeightedAverageInterestRateDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivities" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_4C31BC78E1AD8A9ED639105D953E086D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_3E7FE132F56BDEA8A42B105D953C8019" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_4C31BC78E1AD8A9ED639105D953E086D" xlink:to="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_3E7FE132F56BDEA8A42B105D953C8019" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_A0553A0BEF4A866F3DEE105D953CCAA1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_3E7FE132F56BDEA8A42B105D953C8019" xlink:to="loc_us-gaap_HedgingDesignationAxis_A0553A0BEF4A866F3DEE105D953CCAA1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_A0553A0BEF4A866F3DEE105D953CCAA1" xlink:to="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_A0553A0BEF4A866F3DEE105D953CCAA1" xlink:to="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_F1174E3FC5B20C6AD876105D953C601C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4" xlink:to="loc_us-gaap_NondesignatedMember_F1174E3FC5B20C6AD876105D953C601C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DesignatedAsHedgingInstrumentMember" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_4A4D69BDCBF36DCACC0E105D953D15D8" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_44FC9CAB65E3E65CA3A7105D953C73E4" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_4A4D69BDCBF36DCACC0E105D953D15D8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_12CFC26489DB73ECA2D8105D953D3CD0" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable_3E7FE132F56BDEA8A42B105D953C8019" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_12CFC26489DB73ECA2D8105D953D3CD0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_12CFC26489DB73ECA2D8105D953D3CD0" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_12CFC26489DB73ECA2D8105D953D3CD0" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_A94282DA5A4713880486105D953DCE7C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_A94282DA5A4713880486105D953DCE7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_1A7F655007C5A7D0880B105D953EB034" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4" xlink:to="loc_us-gaap_InterestRateSwapMember_1A7F655007C5A7D0880B105D953EB034" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommodityContractMember" xlink:label="loc_us-gaap_CommodityContractMember_0895C993FC91B93D262D105D953E0D59" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_4743DDD195548F1F42E6105D953D7ED4" xlink:to="loc_us-gaap_CommodityContractMember_0895C993FC91B93D262D105D953E0D59" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeNotionalAmount" xlink:label="loc_us-gaap_DerivativeNotionalAmount_8B16435AC5C85CE3C98D105D953EF620" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_4C31BC78E1AD8A9ED639105D953E086D" xlink:to="loc_us-gaap_DerivativeNotionalAmount_8B16435AC5C85CE3C98D105D953EF620" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet" xlink:label="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_0C4779704AD25CC76792105D953EDB7F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_4C31BC78E1AD8A9ED639105D953E086D" xlink:to="loc_us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet_0C4779704AD25CC76792105D953EDB7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months" xlink:label="loc_us-gaap_PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months_5213D42218A688211B74105D953EF231" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems_4C31BC78E1AD8A9ED639105D953E086D" xlink:to="loc_us-gaap_PriceRiskCashFlowHedgeUnrealizedGainLossToBeReclassifiedDuringNext12Months_5213D42218A688211B74105D953EF231" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesEffectOfDerivativeInstrumentsOnAociAndStatementsOfOperationsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_F5F04B93759F302EF543105D95276BAE" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_F5F04B93759F302EF543105D95276BAE" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_6A9D772A6561FD1DC884105D9523C3D2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_6A9D772A6561FD1DC884105D9523C3D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="loc_us-gaap_HedgingRelationshipDomain_CBC325782F911BE7DB9C105D95232939_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_6A9D772A6561FD1DC884105D9523C3D2" xlink:to="loc_us-gaap_HedgingRelationshipDomain_CBC325782F911BE7DB9C105D95232939_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingRelationshipDomain" xlink:label="loc_us-gaap_HedgingRelationshipDomain_CBC325782F911BE7DB9C105D95232939" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipAxis_6A9D772A6561FD1DC884105D9523C3D2" xlink:to="loc_us-gaap_HedgingRelationshipDomain_CBC325782F911BE7DB9C105D95232939" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashFlowHedgingMember" xlink:label="loc_us-gaap_CashFlowHedgingMember_184FDFC955300093D7FE105D952460EE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingRelationshipDomain_CBC325782F911BE7DB9C105D95232939" xlink:to="loc_us-gaap_CashFlowHedgingMember_184FDFC955300093D7FE105D952460EE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_E5D0C545B9F6555C41A0105D95240A7F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:to="loc_us-gaap_HedgingDesignationAxis_E5D0C545B9F6555C41A0105D95240A7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_4153F8CED1B833263B20105D95243339_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_E5D0C545B9F6555C41A0105D95240A7F" xlink:to="loc_us-gaap_HedgingDesignationDomain_4153F8CED1B833263B20105D95243339_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_4153F8CED1B833263B20105D95243339" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_E5D0C545B9F6555C41A0105D95240A7F" xlink:to="loc_us-gaap_HedgingDesignationDomain_4153F8CED1B833263B20105D95243339" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_6B9E80B9FEE877F2A9EA105D95250D95" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_4153F8CED1B833263B20105D95243339" xlink:to="loc_us-gaap_NondesignatedMember_6B9E80B9FEE877F2A9EA105D95250D95" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_A72F79D59EEB91E7A557105D9525103C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_A72F79D59EEB91E7A557105D9525103C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_A72F79D59EEB91E7A557105D9525103C" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_A72F79D59EEB91E7A557105D9525103C" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_7C665C51FC3881E71E88105D95252B64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923" xlink:to="loc_us-gaap_InterestRateSwapMember_7C665C51FC3881E71E88105D95252B64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_889ACDABCADB62387834105D95259E29" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_889ACDABCADB62387834105D95259E29" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommodityContractMember" xlink:label="loc_us-gaap_CommodityContractMember_99BA56C584946C995407105D9526A3A4" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_A1CAC4D011B46273207E105D9525F923" xlink:to="loc_us-gaap_CommodityContractMember_99BA56C584946C995407105D9526A3A4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_010055442EB66AF0CF74105D95264F17" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossByHedgingRelationshipByIncomeStatementLocationByDerivativeInstrumentRiskTable_26246765A4778BE9435D105D95235E4B" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_010055442EB66AF0CF74105D95264F17" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_010055442EB66AF0CF74105D95264F17" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_010055442EB66AF0CF74105D95264F17" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestExpenseMember" xlink:label="loc_us-gaap_InterestExpenseMember_7244724A35539880AA12105D952677D9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE" xlink:to="loc_us-gaap_InterestExpenseMember_7244724A35539880AA12105D952677D9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherOperatingIncomeExpenseMember" xlink:label="loc_us-gaap_OtherOperatingIncomeExpenseMember_43E93C0C442C205620E7105D9526B437" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE" xlink:to="loc_us-gaap_OtherOperatingIncomeExpenseMember_43E93C0C442C205620E7105D9526B437" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_0E348B16580D46926DE0105D95277993" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_678A996FEFFE3C2D27FC105D9526F4DE" xlink:to="loc_us-gaap_CostOfSalesMember_0E348B16580D46926DE0105D95277993" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax_B57AA57EF08CD60D13E5105D9527B915" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_F5F04B93759F302EF543105D95276BAE" xlink:to="loc_us-gaap_OtherComprehensiveIncomeUnrealizedGainLossOnDerivativesArisingDuringPeriodBeforeTax_B57AA57EF08CD60D13E5105D9527B915" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet" xlink:label="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_872C4668853B499A8AE5105D952797DA" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_F5F04B93759F302EF543105D95276BAE" xlink:to="loc_us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet_872C4668853B499A8AE5105D952797DA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet_585B06CBE744F0AEB566105D95276ECC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeInstrumentsGainLossLineItems_F5F04B93759F302EF543105D95276BAE" xlink:to="loc_us-gaap_DerivativeGainLossOnDerivativeNet_585B06CBE744F0AEB566105D95276ECC" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesFairValuesOfDerivativeInstrumentsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativesFairValueLineItems" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_80378AE22F4B6D699BE7105D9531F1A6" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable" xlink:label="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_14C76DEFF9684DC9EA11105D952D2480" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_80378AE22F4B6D699BE7105D9531F1A6" xlink:to="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_14C76DEFF9684DC9EA11105D952D2480" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis_0E1232394B4450D65C1D105D952DA018" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_14C76DEFF9684DC9EA11105D952D2480" xlink:to="loc_us-gaap_HedgingDesignationAxis_0E1232394B4450D65C1D105D952DA018" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_0E1232394B4450D65C1D105D952DA018" xlink:to="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_0E1232394B4450D65C1D105D952DA018" xlink:to="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DesignatedAsHedgingInstrumentMember" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_843D578284ABB1A19779105D952E6B00" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_843D578284ABB1A19779105D952E6B00" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember_28D41523C98A9CA0C13A105D952E519E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_027A830F5150743CA227105D952E08D6" xlink:to="loc_us-gaap_NondesignatedMember_28D41523C98A9CA0C13A105D952E519E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_82A344E3D4D64D4FB644105D952E3D5F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_14C76DEFF9684DC9EA11105D952D2480" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_82A344E3D4D64D4FB644105D952E3D5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_82A344E3D4D64D4FB644105D952E3D5F" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_82A344E3D4D64D4FB644105D952E3D5F" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_67D7FABD10A7FA1F4F33105D952FEA49" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D" xlink:to="loc_us-gaap_InterestRateSwapMember_67D7FABD10A7FA1F4F33105D952FEA49" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_ABC64C10F8801CAABF70105D952FDA39" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_ABC64C10F8801CAABF70105D952FDA39" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommodityContractMember" xlink:label="loc_us-gaap_CommodityContractMember_2C094452065F9F2A92A5105D952F8846" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_E86A64FF8ECBB63EFA1E105D952FC61D" xlink:to="loc_us-gaap_CommodityContractMember_2C094452065F9F2A92A5105D952F8846" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_CB52C01C1B97DAE3C808105D952F2462" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValuesDerivativesBalanceSheetLocationByDerivativeContractTypeByHedgingDesignationTable_14C76DEFF9684DC9EA11105D952D2480" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_CB52C01C1B97DAE3C808105D952F2462" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_CB52C01C1B97DAE3C808105D952F2462" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_CB52C01C1B97DAE3C808105D952F2462" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember" xlink:label="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_B50D965682C665C44E9F105D9530E083" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:to="loc_us-gaap_PrepaidExpensesAndOtherCurrentAssetsMember_B50D965682C665C44E9F105D9530E083" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsMember" xlink:label="loc_us-gaap_OtherAssetsMember_455B2DA48263A17AA979105D95307161" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:to="loc_us-gaap_OtherAssetsMember_455B2DA48263A17AA979105D95307161" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherCurrentLiabilitiesMember" xlink:label="loc_us-gaap_OtherCurrentLiabilitiesMember_F04E25EBF7C48BFBB6A2105D9530519A" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:to="loc_us-gaap_OtherCurrentLiabilitiesMember_F04E25EBF7C48BFBB6A2105D9530519A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesMember" xlink:label="loc_us-gaap_OtherLiabilitiesMember_B1F033A65E9D1B4446F3105D95309475" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_DB80E4CBC5509ACE47D4105D95304942" xlink:to="loc_us-gaap_OtherLiabilitiesMember_B1F033A65E9D1B4446F3105D95309475" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeAsset" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_7C5841E33245F02E8702105D95318D8F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_80378AE22F4B6D699BE7105D9531F1A6" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeAsset_7C5841E33245F02E8702105D95318D8F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeLiability" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_4D08886417BE0569B915105D95312466" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_80378AE22F4B6D699BE7105D9531F1A6" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeLiability_4D08886417BE0569B915105D95312466" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeFairValueOfDerivativeNet" xlink:label="loc_us-gaap_DerivativeFairValueOfDerivativeNet_E37A047E110B9B2900CE105D95313E47" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_80378AE22F4B6D699BE7105D9531F1A6" xlink:to="loc_us-gaap_DerivativeFairValueOfDerivativeNet_E37A047E110B9B2900CE105D95313E47" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesOutstandingCommodityContractsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeLineItems" xlink:label="loc_us-gaap_DerivativeLineItems_86B974D07AC9879FB6100C8DB922181B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeTable" xlink:label="loc_us-gaap_DerivativeTable_2481D22525CFDE2375D50C8DB920C9C4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_86B974D07AC9879FB6100C8DB922181B" xlink:to="loc_us-gaap_DerivativeTable_2481D22525CFDE2375D50C8DB920C9C4" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_B1319455F0FCBA1DED420C8DB92035E5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_2481D22525CFDE2375D50C8DB920C9C4" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_B1319455F0FCBA1DED420C8DB92035E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_B1319455F0FCBA1DED420C8DB92035E5" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_B1319455F0FCBA1DED420C8DB92035E5" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_UreaMember" xlink:label="loc_smg_UreaMember_59A4F237CE1C2EB50B2D0C8DB9218711" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:to="loc_smg_UreaMember_59A4F237CE1C2EB50B2D0C8DB9218711" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd#sic_Z2821" xlink:label="loc_sic_Z2821_C8EB084B4DC6D124A47A0C8DB9219981" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:to="loc_sic_Z2821_C8EB084B4DC6D124A47A0C8DB9219981" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DieselFuelMember" xlink:label="loc_smg_DieselFuelMember_9F29836466CE005879970C8DB921CF3F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:to="loc_smg_DieselFuelMember_9F29836466CE005879970C8DB921CF3F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_HeatingOilMember" xlink:label="loc_srt_HeatingOilMember_674EA269F8F27B105B720C8DB9214A89" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_9ED18D22B241616295660C8DB92011FA" xlink:to="loc_srt_HeatingOilMember_674EA269F8F27B105B720C8DB9214A89" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeNonmonetaryNotionalAmountMass" xlink:label="loc_us-gaap_DerivativeNonmonetaryNotionalAmountMass_582ED22DB33834F6E5BF0C8DB9227640" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_86B974D07AC9879FB6100C8DB922181B" xlink:to="loc_us-gaap_DerivativeNonmonetaryNotionalAmountMass_582ED22DB33834F6E5BF0C8DB9227640" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeNonmonetaryNotionalAmountVolume" xlink:label="loc_us-gaap_DerivativeNonmonetaryNotionalAmountVolume_42E4D1F8FD4D6AE5D3830C8DB92212BE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_86B974D07AC9879FB6100C8DB922181B" xlink:to="loc_us-gaap_DerivativeNonmonetaryNotionalAmountVolume_42E4D1F8FD4D6AE5D3830C8DB92212BE" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DerivativeInstrumentsAndHedgingActivitiesTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DiscontinuedOperations" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DiscontinuedOperationsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_6E38B1554BB268B7357A0B433C151247" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_6E38B1554BB268B7357A0B433C151247" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_5FB34A53FC1A3F4E08190B433C155182" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_6E38B1554BB268B7357A0B433C151247" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_5FB34A53FC1A3F4E08190B433C155182" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_5FB34A53FC1A3F4E08190B433C155182" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain" xlink:label="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis_5FB34A53FC1A3F4E08190B433C155182" xlink:to="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InternationalBusinessMember" xlink:label="loc_smg_InternationalBusinessMember_040D982BB7F5D5B89B430B433C16FBA7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081" xlink:to="loc_smg_InternationalBusinessMember_040D982BB7F5D5B89B430B433C16FBA7" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_WildBirdFoodMember" xlink:label="loc_smg_WildBirdFoodMember_D1F9120319B4AB156AFF0B433C1662BC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupsIncludingDiscontinuedOperationsNameDomain_19712FCEB7D39452BDE30B433C15A081" xlink:to="loc_smg_WildBirdFoodMember_D1F9120319B4AB156AFF0B433C1662BC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal" xlink:label="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_86E1E2F8A45478BC2F160B433C1669BA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_DisposalGroupNotDiscontinuedOperationGainLossOnDisposal_86E1E2F8A45478BC2F160B433C1669BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringAndRelatedCostIncurredCost" xlink:label="loc_us-gaap_RestructuringAndRelatedCostIncurredCost_6A5908EF23394FB164120B433C16AC14" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_RestructuringAndRelatedCostIncurredCost_6A5908EF23394FB164120B433C16AC14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GainLossRelatedToLitigationSettlement" xlink:label="loc_us-gaap_GainLossRelatedToLitigationSettlement_316ECFB3B613B9DFAA160B433C173EBF" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_GainLossRelatedToLitigationSettlement_316ECFB3B613B9DFAA160B433C173EBF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InsuranceRecoveries" xlink:label="loc_us-gaap_InsuranceRecoveries_D41F6801EB034DE7328F0B433C1718CC" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_InsuranceRecoveries_D41F6801EB034DE7328F0B433C1718CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingencyLossInPeriod" xlink:label="loc_us-gaap_LossContingencyLossInPeriod_8969A6179A3D084A685C0B433C17EB2E" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_LossContingencyLossInPeriod_8969A6179A3D084A685C0B433C17EB2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingencyAccrualAtCarryingValue" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_A9FB48F17B9EB6B0F2070B433C171B76" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_LossContingencyAccrualAtCarryingValue_A9FB48F17B9EB6B0F2070B433C171B76" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations" xlink:label="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_8BCECE7C1A9AEE4AF8330B433C17ED65" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations_8BCECE7C1A9AEE4AF8330B433C17ED65" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations" xlink:label="loc_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_8613E3339A76D9B9F0370B433C185B33" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_B07361D74176F0B77C790B433C16880A" xlink:to="loc_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_8613E3339A76D9B9F0370B433C185B33" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DiscontinuedOperationsSummaryOfIncomeFromDiscontinuedOperationsDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/DiscontinuedOperationsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/Equity" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/EquityAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityClassOfTreasuryStockLineItems" xlink:label="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ClassOfTreasuryStockTable" xlink:label="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_65E8E712B832566402B41688184BB14B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_65E8E712B832566402B41688184BB14B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_BD2381D982A2BAA4FD4C1688184B98C1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_65E8E712B832566402B41688184BB14B" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_BD2381D982A2BAA4FD4C1688184B98C1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_BD2381D982A2BAA4FD4C1688184B98C1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_65E8E712B832566402B41688184BB14B" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_BD2381D982A2BAA4FD4C1688184B98C1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_120FBC2B68B4BA738DD91688184BB91F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_BD2381D982A2BAA4FD4C1688184B98C1" xlink:to="loc_us-gaap_SubsequentEventMember_120FBC2B68B4BA738DD91688184BB91F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_63C716AA8BDB6603A9F81688184C6C68" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_63C716AA8BDB6603A9F81688184C6C68" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_5E0A9839F2A0328B53211688184CA1CF_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_63C716AA8BDB6603A9F81688184C6C68" xlink:to="loc_us-gaap_TypeOfAdoptionMember_5E0A9839F2A0328B53211688184CA1CF_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_5E0A9839F2A0328B53211688184CA1CF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_63C716AA8BDB6603A9F81688184C6C68" xlink:to="loc_us-gaap_TypeOfAdoptionMember_5E0A9839F2A0328B53211688184CA1CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingStandardsUpdate201609Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201609Member_37B561D783A9F1A5AEEB1688184C9267" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_5E0A9839F2A0328B53211688184CA1CF" xlink:to="loc_us-gaap_AccountingStandardsUpdate201609Member_37B561D783A9F1A5AEEB1688184C9267" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_7DECBB092187D6F2F7D51688184CC4EC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_7DECBB092187D6F2F7D51688184CC4EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7DECBB092187D6F2F7D51688184CC4EC" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7DECBB092187D6F2F7D51688184CC4EC" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SunlightSupplyMember" xlink:label="loc_smg_SunlightSupplyMember_C8D8099DA217388C91BB1688184D79E4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26" xlink:to="loc_smg_SunlightSupplyMember_C8D8099DA217388C91BB1688184D79E4" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_GavitaHoldingsB.V.Member" xlink:label="loc_smg_GavitaHoldingsB.V.Member_63A7D8BC29FC469383C71688184D5845" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_B3DB728439D6A915DE821688184CED26" xlink:to="loc_smg_GavitaHoldingsB.V.Member_63A7D8BC29FC469383C71688184D5845" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_9CCD5867B3FBF6CB0AC61688184D6BB1" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_6F23D76C418D65C9B0861688184A1ED9" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_9CCD5867B3FBF6CB0AC61688184D6BB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_9CCD5867B3FBF6CB0AC61688184D6BB1" xlink:to="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_9CCD5867B3FBF6CB0AC61688184D6BB1" xlink:to="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_E99E6C3058F0E6A305551688184EAF59" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7" xlink:to="loc_us-gaap_TreasuryStockMember_E99E6C3058F0E6A305551688184EAF59" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_B3A678B0C37C2E1A4FBC1688184E9945" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_73471D817E954DC64E491688184D26A7" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_B3A678B0C37C2E1A4FBC1688184E9945" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax_08085A7E7DEA672568711688184E8A37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossDefinedBenefitPensionAndOtherPostretirementPlansNetOfTax_08085A7E7DEA672568711688184E8A37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax_C9E1BDC33B544840AFB81688184F6A99" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansBeforeReclassificationAdjustmentsTax_C9E1BDC33B544840AFB81688184F6A99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_0B9D09061F4BBFB3FAE01688184F26D1" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax_0B9D09061F4BBFB3FAE01688184F26D1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" xlink:label="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax_0751D94C839401AA1DA41688184FBEC7" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax_0751D94C839401AA1DA41688184FBEC7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax_3CBF035D26B25BCDD5591688184FB6E4" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax_3CBF035D26B25BCDD5591688184FB6E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_EFBE91673FE6AECDF7871688184F5027" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_EFBE91673FE6AECDF7871688184F5027" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchaseProgramAuthorizedAmount1" xlink:label="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_E04D7EE07E1C274CD38B168818504DEA" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_E04D7EE07E1C274CD38B168818504DEA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchaseProgramPeriodInForce1" xlink:label="loc_us-gaap_StockRepurchaseProgramPeriodInForce1_99FF98FDAE1D948F147816881850144E" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_StockRepurchaseProgramPeriodInForce1_99FF98FDAE1D948F147816881850144E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_AdditionalSharesAuthorizedForRepurchaseValue" xlink:label="loc_smg_AdditionalSharesAuthorizedForRepurchaseValue_F66C46883D61E74146FF1688185081AA" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_smg_AdditionalSharesAuthorizedForRepurchaseValue_F66C46883D61E74146FF1688185081AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchasedDuringPeriodShares" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares_11A97FA01A4BC29BECB816881850E595" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodShares_11A97FA01A4BC29BECB816881850E595" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockRepurchasedDuringPeriodValue" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodValue_7C45E2877F520B36234D16881850AA86" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_StockRepurchasedDuringPeriodValue_7C45E2877F520B36234D16881850AA86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesTreasuryStockReissued" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesTreasuryStockReissued_D30E830517589FC2A3FE168818515930" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesTreasuryStockReissued_D30E830517589FC2A3FE168818515930" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_EconomicInterestAcquired" xlink:label="loc_smg_EconomicInterestAcquired_8892E928E48DE4F112AF16881851032E" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_smg_EconomicInterestAcquired_8892E928E48DE4F112AF16881851032E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_8E03EAA8D43FECA00A5D16881851F7E6" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_8E03EAA8D43FECA00A5D16881851F7E6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForPreviousAcquisition" xlink:label="loc_us-gaap_PaymentsForPreviousAcquisition_023B631E14B8A50FCC9216881851374C" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_PaymentsForPreviousAcquisition_023B631E14B8A50FCC9216881851374C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue_A1A2C37C0B4888C201A416881851B19D" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_LongTermDebtFairValue_A1A2C37C0B4888C201A416881851B19D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_MinorityInterestDecreaseFromRedemptions" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromRedemptions_195B701583F86D51685216881851B232" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromRedemptions_195B701583F86D51685216881851B232" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_3A87B7CAA648602DE42E16881852ED96" xlink:type="locator" />
    <link:definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_B0247F99CB7DE0C468581688184E0D51" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_3A87B7CAA648602DE42E16881852ED96" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EquityShareBasedAwardsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_76F342A23E63BEC9EADA0BA31BE3AB3D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_76F342A23E63BEC9EADA0BA31BE3AB3D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_C378CA01CAADB659812F0BA31BE32164_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_76F342A23E63BEC9EADA0BA31BE3AB3D" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_C378CA01CAADB659812F0BA31BE32164_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_C378CA01CAADB659812F0BA31BE32164" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_76F342A23E63BEC9EADA0BA31BE3AB3D" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_C378CA01CAADB659812F0BA31BE32164" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_9A39C956CEE638C097B60BA31BE3EB2D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_C378CA01CAADB659812F0BA31BE32164" xlink:to="loc_us-gaap_SubsequentEventMember_9A39C956CEE638C097B60BA31BE3EB2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanAxis" xlink:label="loc_us-gaap_RestructuringPlanAxis_DFB766CEEBF7DC7608E10BA31BE4C285" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_us-gaap_RestructuringPlanAxis_DFB766CEEBF7DC7608E10BA31BE4C285" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_6B3E9CA5A8930BBCC2250BA31BE4FA98_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_DFB766CEEBF7DC7608E10BA31BE4C285" xlink:to="loc_us-gaap_RestructuringPlanDomain_6B3E9CA5A8930BBCC2250BA31BE4FA98_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_6B3E9CA5A8930BBCC2250BA31BE4FA98" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_DFB766CEEBF7DC7608E10BA31BE4C285" xlink:to="loc_us-gaap_RestructuringPlanDomain_6B3E9CA5A8930BBCC2250BA31BE4FA98" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProjectFocusMember" xlink:label="loc_smg_ProjectFocusMember_BC0EE1EE033117C2FA7C0BA31BE45C8B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_6B3E9CA5A8930BBCC2250BA31BE4FA98" xlink:to="loc_smg_ProjectFocusMember_BC0EE1EE033117C2FA7C0BA31BE45C8B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_3C5ACF842495230343AC0BA31BE584EE" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_3C5ACF842495230343AC0BA31BE584EE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_631707925027EE4554C50BA31BE52901_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3C5ACF842495230343AC0BA31BE584EE" xlink:to="loc_us-gaap_SegmentDomain_631707925027EE4554C50BA31BE52901_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_631707925027EE4554C50BA31BE52901" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3C5ACF842495230343AC0BA31BE584EE" xlink:to="loc_us-gaap_SegmentDomain_631707925027EE4554C50BA31BE52901" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_HawthorneMember" xlink:label="loc_smg_HawthorneMember_764BC2FD1C32396298B90BA31BE5074A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_631707925027EE4554C50BA31BE52901" xlink:to="loc_smg_HawthorneMember_764BC2FD1C32396298B90BA31BE5074A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_1B28645FC92F1C4C76100BA31BE5E287" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_srt_RangeAxis_1B28645FC92F1C4C76100BA31BE5E287" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_1B28645FC92F1C4C76100BA31BE5E287" xlink:to="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_1B28645FC92F1C4C76100BA31BE5E287" xlink:to="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember_2931D92192B60E7615470BA31BE6BF2E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F" xlink:to="loc_srt_MinimumMember_2931D92192B60E7615470BA31BE6BF2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_C753F22B5347AE85CBCF0BA31BE6C9F5" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_BAAA504B3CBF085B5BE00BA31BE57D7F" xlink:to="loc_srt_MaximumMember_C753F22B5347AE85CBCF0BA31BE6C9F5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_C7219B0F42E9056A0CA50BA31BE6B4D6" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_us-gaap_AwardTypeAxis_C7219B0F42E9056A0CA50BA31BE6B4D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_C7219B0F42E9056A0CA50BA31BE6B4D6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_C7219B0F42E9056A0CA50BA31BE6B4D6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_26428BEE7A911A686D980BA31BE78C71" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_26428BEE7A911A686D980BA31BE78C71" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember_ED0D3791D34A5A6B45540BA31BE7B437" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF" xlink:to="loc_us-gaap_PerformanceSharesMember_ED0D3791D34A5A6B45540BA31BE7B437" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DeferredStockUnitsMember" xlink:label="loc_smg_DeferredStockUnitsMember_2C18035277B0420FDE120BA31BE7E5F2" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_D8887F2E925CB011BA930BA31BE6F5AF" xlink:to="loc_smg_DeferredStockUnitsMember_2C18035277B0420FDE120BA31BE7E5F2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srt_TitleOfIndividualAxis_9903CC2671837C73AB890BA31BE77693" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_B70562D5BBE02DADE9860BA31BE2EE7F" xlink:to="loc_srt_TitleOfIndividualAxis_9903CC2671837C73AB890BA31BE77693" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_TitleOfIndividualAxis_9903CC2671837C73AB890BA31BE77693" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_TitleOfIndividualAxis_9903CC2671837C73AB890BA31BE77693" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_KeyEmployeesMember" xlink:label="loc_smg_KeyEmployeesMember_6D8A24225F65857A89B20BA31BE8252F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E" xlink:to="loc_smg_KeyEmployeesMember_6D8A24225F65857A89B20BA31BE8252F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_DirectorMember" xlink:label="loc_srt_DirectorMember_B7E4727B560925659A810BA31BE85E06" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E" xlink:to="loc_srt_DirectorMember_B7E4727B560925659A810BA31BE85E06" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_BoardOfDirectorsChairmanMember" xlink:label="loc_srt_BoardOfDirectorsChairmanMember_BA56AB5D8021DF0D3EB10BA31BE84B92" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_5426FD788CC1D27EE51E0BA31BE7A31E" xlink:to="loc_srt_BoardOfDirectorsChairmanMember_BA56AB5D8021DF0D3EB10BA31BE84B92" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_391656DA5FDA177643E20BA31BE9A5BD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_391656DA5FDA177643E20BA31BE9A5BD" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue" xlink:label="loc_smg_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue_BD18399116C221DAAE160BA31BE97A32" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:to="loc_smg_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodFairValue_BD18399116C221DAAE160BA31BE97A32" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_25CE073C5F82BA8BAE0A0BA31BE9B8AA" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage_25CE073C5F82BA8BAE0A0BA31BE9B8AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_12EEE921CD4A34B8A94B0BA31BE94A67" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_19C74200429328CC12E30BA31BE88A8D" xlink:to="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensation_12EEE921CD4A34B8A94B0BA31BE94A67" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EquitySummaryOfChangesInEquityDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_1903C4FE1E79DDD62907105D957BA185" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_A0568D0C2C1028097E83105D957976E1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_1903C4FE1E79DDD62907105D957BA185" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_A0568D0C2C1028097E83105D957976E1" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_471E66EB221DA8A02CFE105D95792F91" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_A0568D0C2C1028097E83105D957976E1" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_471E66EB221DA8A02CFE105D95792F91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_471E66EB221DA8A02CFE105D95792F91" xlink:to="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_471E66EB221DA8A02CFE105D95792F91" xlink:to="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_92C2011C2274E42F7B8A105D957A7016" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_92C2011C2274E42F7B8A105D957A7016" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_07439CBB3D0F41E5BBCC105D957A8F2D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_RetainedEarningsMember_07439CBB3D0F41E5BBCC105D957A8F2D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TreasuryStockMember" xlink:label="loc_us-gaap_TreasuryStockMember_0FDB597B5D303C7F6F9A105D957A2E2F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_TreasuryStockMember_0FDB597B5D303C7F6F9A105D957A2E2F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1A916EC6920E3CF236F3105D957BAB2A" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_1A916EC6920E3CF236F3105D957BAB2A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ParentMember" xlink:label="loc_us-gaap_ParentMember_3A5FEF77056ECD45928D105D957B40D2" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_ParentMember_3A5FEF77056ECD45928D105D957B40D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember_9080AC78E78E7C8587B7105D957B31CE" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_0D152DE13B1A9CC13ACB105D957A7BFA" xlink:to="loc_us-gaap_NoncontrollingInterestMember_9080AC78E78E7C8587B7105D957B31CE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommonStockDividendsPerShareDeclared" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_FCEE2F5D4BD94965A001105D957BE2E4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_1903C4FE1E79DDD62907105D957BA185" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_FCEE2F5D4BD94965A001105D957BE2E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_1903C4FE1E79DDD62907105D957BA185" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_B1FF8C6CA76A7E46CF23105D957C1AC2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_StockholdersEquity_B1FF8C6CA76A7E46CF23105D957C1AC2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaap_MinorityInterest_3CDFE0BD1967C8845773105D957CC305" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_MinorityInterest_3CDFE0BD1967C8845773105D957CC305" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_44B192670ED4CDF41EF0105D957C093F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_44B192670ED4CDF41EF0105D957C093F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification" xlink:label="loc_us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification_D5236150490F266C9249105D957CC9D5" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification_D5236150490F266C9249105D957CC9D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_1FFD8C617451DB8D4BB1105D957D6949" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_ProfitLoss_1FFD8C617451DB8D4BB1105D957D6949" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_F66DA46967012F52EACA105D957D20AC" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_F66DA46967012F52EACA105D957D20AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_EE619CFEBC7AD28E1DBB105D957D229E" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_EE619CFEBC7AD28E1DBB105D957D229E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Dividends" xlink:label="loc_us-gaap_Dividends_8AA4FF24A49C63DD3F02105D957DC068" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_Dividends_8AA4FF24A49C63DD3F02105D957DC068" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_2334CFF136C8895CEA41105D957DCF78" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_2334CFF136C8895CEA41105D957DCF78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_00DD991843112F5891A0105D957D9AA4" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_00DD991843112F5891A0105D957D9AA4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_MinorityInterestDecreaseFromRedemptions" xlink:label="loc_us-gaap_MinorityInterestDecreaseFromRedemptions_98788931D6A6DBD03B7B105D957E279A" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_FBF850EEF0983A830508105D957C9307" xlink:to="loc_us-gaap_MinorityInterestDecreaseFromRedemptions_98788931D6A6DBD03B7B105D957E279A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EquityTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/EquityTotalShareBasedCompensationDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/FairValueMeasurements" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/FairValueMeasurementsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_6BECB6AE3C740E03120A1590FAF5CA61" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_6BECB6AE3C740E03120A1590FAF5CA61" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_C5D2D22AC37C8FC1D5811590FAEDEABA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_DebtInstrumentAxis_C5D2D22AC37C8FC1D5811590FAEDEABA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_C5D2D22AC37C8FC1D5811590FAEDEABA" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_C5D2D22AC37C8FC1D5811590FAEDEABA" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes4.50PercentDue2029MemberDomain" xlink:label="loc_smg_SeniorNotes4.50PercentDue2029MemberDomain_CBCB8D38A4F740F17BED1590FAEDD79B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D" xlink:to="loc_smg_SeniorNotes4.50PercentDue2029MemberDomain_CBCB8D38A4F740F17BED1590FAEDD79B" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_07CEDDD70AD72112D5BD1590FAEE3A01" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_07CEDDD70AD72112D5BD1590FAEE3A01" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotesFiveandAQuarterPercentMember" xlink:label="loc_smg_SeniorNotesFiveandAQuarterPercentMember_422F1AE1ECD76939B4691590FAEEFDF3" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_6E2AFB2226F2CE6EB99C1590FAEDED5D" xlink:to="loc_smg_SeniorNotesFiveandAQuarterPercentMember_422F1AE1ECD76939B4691590FAEEFDF3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_B36C56DBA381653687851590FAEE037B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_CreditFacilityAxis_B36C56DBA381653687851590FAEE037B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_B36C56DBA381653687851590FAEE037B" xlink:to="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_B36C56DBA381653687851590FAEE037B" xlink:to="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TermLoanMember" xlink:label="loc_smg_TermLoanMember_BF57E82803851BF0C1151590FAEEC57B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD" xlink:to="loc_smg_TermLoanMember_BF57E82803851BF0C1151590FAEEC57B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_11B75CFB8424B21637391590FAEE1F5F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_143F2DBB1D57C8D9E2791590FAEEA6CD" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_11B75CFB8424B21637391590FAEE1F5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_CC41B39416FDBEB83B021590FAEF1FB2" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_CC41B39416FDBEB83B021590FAEF1FB2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_CC41B39416FDBEB83B021590FAEF1FB2" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_CC41B39416FDBEB83B021590FAEF1FB2" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_AF5A44254917CD127C2C1590FAEF95B0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:to="loc_us-gaap_SeniorNotesMember_AF5A44254917CD127C2C1590FAEF95B0" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MasterAccountsReceivablePurchaseAgreementMember" xlink:label="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_433BF00043BDB16DE3CB1590FAF0AD50" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:to="loc_smg_MasterAccountsReceivablePurchaseAgreementMember_433BF00043BDB16DE3CB1590FAF0AD50" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_OtherLongtermDebtMember" xlink:label="loc_smg_OtherLongtermDebtMember_C8214437F989BC90C8451590FAF0E9FE" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:to="loc_smg_OtherLongtermDebtMember_C8214437F989BC90C8451590FAF0E9FE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember_9A4F6C6970A21F9B7F481590FAF0EF62" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_760FC6EEE357360CB91F1590FAEF22C0" xlink:to="loc_us-gaap_LineOfCreditMember_9A4F6C6970A21F9B7F481590FAF0EF62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_C6ECF6248204B4372FE71590FAF0AFD5" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_C6ECF6248204B4372FE71590FAF0AFD5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_AB406F99DD86D5FD91531590FAF0E031_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_C6ECF6248204B4372FE71590FAF0AFD5" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_AB406F99DD86D5FD91531590FAF0E031_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueDisclosureItemAmountsDomain" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D0E52FC0EDF38BD9F6501590FAF04DBB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_C6ECF6248204B4372FE71590FAF0AFD5" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D0E52FC0EDF38BD9F6501590FAF04DBB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_AB406F99DD86D5FD91531590FAF0E031" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D0E52FC0EDF38BD9F6501590FAF04DBB" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_AB406F99DD86D5FD91531590FAF0E031" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_1F6A2EB0CD759759BD911590FAF1CA66" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D0E52FC0EDF38BD9F6501590FAF04DBB" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_1F6A2EB0CD759759BD911590FAF1CA66" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_2CF72E666F3270E4A8821590FAF1BC99" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_D0E52FC0EDF38BD9F6501590FAF04DBB" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_2CF72E666F3270E4A8821590FAF1BC99" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_B7A0589BF0AE2CE762E91590FAF1B19B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_B7A0589BF0AE2CE762E91590FAF1B19B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_671B507EF8B959F6EB5F1590FAF1F136_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_B7A0589BF0AE2CE762E91590FAF1B19B" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_671B507EF8B959F6EB5F1590FAF1F136_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_671B507EF8B959F6EB5F1590FAF1F136" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_B7A0589BF0AE2CE762E91590FAF1B19B" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_671B507EF8B959F6EB5F1590FAF1F136" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_GavitaHoldingsB.V.Member" xlink:label="loc_smg_GavitaHoldingsB.V.Member_91599F0EB8858F79F5961590FAF1FEB0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_671B507EF8B959F6EB5F1590FAF1F136" xlink:to="loc_smg_GavitaHoldingsB.V.Member_91599F0EB8858F79F5961590FAF1FEB0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueByMeasurementFrequencyAxis" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_904972929FACB8443C661590FAF2F645" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_904972929FACB8443C661590FAF2F645" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_CFDB730FB9A38359906D1590FAF29F47_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_904972929FACB8443C661590FAF2F645" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_CFDB730FB9A38359906D1590FAF29F47_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementFrequencyDomain" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_CFDB730FB9A38359906D1590FAF29F47" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_904972929FACB8443C661590FAF2F645" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_CFDB730FB9A38359906D1590FAF29F47" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementsRecurringMember" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_684F47A8E7550B8AD45C1590FAF2534B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_CFDB730FB9A38359906D1590FAF29F47" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_684F47A8E7550B8AD45C1590FAF2534B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_9F3210E2FF4E483935031590FAF309B0" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_9F3210E2FF4E483935031590FAF309B0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_9F3210E2FF4E483935031590FAF309B0" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_9F3210E2FF4E483935031590FAF309B0" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_2835BA87F79A3EE44BB81590FAF38F5F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_2835BA87F79A3EE44BB81590FAF38F5F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_A0E176FDB1B46B1BB6651590FAF3024F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_A0E176FDB1B46B1BB6651590FAF3024F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_03D41F0C1183F247F0431590FAF369A1" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_C525CF33BA4275927C461590FAF3624D" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_03D41F0C1183F247F0431590FAF369A1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_6BA98DA1459035A8F5201590FAF49189" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_DA2106BB21BFB35572871590FAEC2C8C" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_6BA98DA1459035A8F5201590FAF49189" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_6BA98DA1459035A8F5201590FAF49189" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_6BA98DA1459035A8F5201590FAF49189" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestRateSwapMember" xlink:label="loc_us-gaap_InterestRateSwapMember_72DE6A28594BC8255AD11590FAF47F7C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD" xlink:to="loc_us-gaap_InterestRateSwapMember_72DE6A28594BC8255AD11590FAF47F7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_C8C8C312D3979A2A5F8B1590FAF49F3E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_C8C8C312D3979A2A5F8B1590FAF49F3E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CommodityContractMember" xlink:label="loc_us-gaap_CommodityContractMember_3C83F16A9531AFA858411590FAF57F19" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_53F7F47C8F80E1CFCB151590FAF460BD" xlink:to="loc_us-gaap_CommodityContractMember_3C83F16A9531AFA858411590FAF57F19" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsFairValueDisclosureAbstract" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_6BECB6AE3C740E03120A1590FAF5CA61" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_E9CF15C5CA44F5767CAF1590FAF5A6C3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_E9CF15C5CA44F5767CAF1590FAF5A6C3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeAssets" xlink:label="loc_us-gaap_DerivativeAssets_E194D7D2BB26F2D9310B1590FAF51ADB" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:to="loc_us-gaap_DerivativeAssets_E194D7D2BB26F2D9310B1590FAF51ADB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsFairValueDisclosure" xlink:label="loc_us-gaap_OtherAssetsFairValueDisclosure_93927EB47993F834FBFA1590FAF62862" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:to="loc_us-gaap_OtherAssetsFairValueDisclosure_93927EB47993F834FBFA1590FAF62862" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure_409A545FF370E01124241590FAF64EA0" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_81CD2053EFBC491860EE1590FAF5FC64" xlink:to="loc_us-gaap_AssetsFairValueDisclosure_409A545FF370E01124241590FAF64EA0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_6BECB6AE3C740E03120A1590FAF5CA61" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DerivativeLiabilities" xlink:label="loc_us-gaap_DerivativeLiabilities_563767610ADB262E46771590FAF6FFE8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:to="loc_us-gaap_DerivativeLiabilities_563767610ADB262E46771590FAF6FFE8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue_5C3F3CFB255C6F1184281590FAF6A7AC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:to="loc_us-gaap_LongTermDebtFairValue_5C3F3CFB255C6F1184281590FAF6A7AC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesFairValueDisclosure" xlink:label="loc_us-gaap_OtherLiabilitiesFairValueDisclosure_6E6C85600C76F545C0A21590FAF709A4" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:to="loc_us-gaap_OtherLiabilitiesFairValueDisclosure_6E6C85600C76F545C0A21590FAF709A4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure_B9A13AB750F9B527ED4D1590FAF7ED18" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_CA50CE90C1E6DC0BE4C51590FAF6E750" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosure_B9A13AB750F9B527ED4D1590FAF7ED18" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FairValueMeasurementsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantors" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_FD68E13B085F609054A1105D946F9B43" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:to="loc_us-gaap_DebtInstrumentAxis_FD68E13B085F609054A1105D946F9B43" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_FD68E13B085F609054A1105D946F9B43" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_FD68E13B085F609054A1105D946F9B43" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember" xlink:label="loc_smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember_841B562FC53329C7C7ED105D9470FB3E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:to="loc_smg_FifthAmendedAndRestatedSeniorSecuredCreditAgreementMember_841B562FC53329C7C7ED105D9470FB3E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_D8B07103223BA4C03415105D94701E6F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_D8B07103223BA4C03415105D94701E6F" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotesFiveandAQuarterPercentMember" xlink:label="loc_smg_SeniorNotesFiveandAQuarterPercentMember_35944BBAB0172841E940105D9470B9AF" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:to="loc_smg_SeniorNotesFiveandAQuarterPercentMember_35944BBAB0172841E940105D9470B9AF" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes4.500Due2029Member" xlink:label="loc_smg_SeniorNotes4.500Due2029Member_7E1DE9114EDAC46D5AE0105D9470E241" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_1E434BA99F3602726975105D946F0AF1" xlink:to="loc_smg_SeniorNotes4.500Due2029Member_7E1DE9114EDAC46D5AE0105D9470E241" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_ABFFF8A4BCAD7A977AB2105D9470F781" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_ABFFF8A4BCAD7A977AB2105D9470F781" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_ABFFF8A4BCAD7A977AB2105D9470F781" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_ABFFF8A4BCAD7A977AB2105D9470F781" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember_65DE4B7D5A3684760ACB105D94713EB6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD" xlink:to="loc_us-gaap_LineOfCreditMember_65DE4B7D5A3684760ACB105D94713EB6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_5F11319D06FBE3911B2C105D947174ED" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_35F6870998C539DDF6E4105D947065BD" xlink:to="loc_us-gaap_SeniorNotesMember_5F11319D06FBE3911B2C105D947174ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_922C5DDB1DE52157019D105D94717ED4" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:to="loc_srt_ConsolidationItemsAxis_922C5DDB1DE52157019D105D94717ED4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_37FC05D5897BB71A3BB7105D94715F81_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_922C5DDB1DE52157019D105D94717ED4" xlink:to="loc_srt_ConsolidationItemsDomain_37FC05D5897BB71A3BB7105D94715F81_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_37FC05D5897BB71A3BB7105D94715F81" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_922C5DDB1DE52157019D105D94717ED4" xlink:to="loc_srt_ConsolidationItemsDomain_37FC05D5897BB71A3BB7105D94715F81" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ReportableLegalEntitiesMember" xlink:label="loc_srt_ReportableLegalEntitiesMember_F7FC03AFCC1EF40092F3105D94721CA9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_37FC05D5897BB71A3BB7105D94715F81" xlink:to="loc_srt_ReportableLegalEntitiesMember_F7FC03AFCC1EF40092F3105D94721CA9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_547239B700B0BCD3D8E8105D9472F249" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_4F82C7B23C1D14837DD4105D946F1C8A" xlink:to="loc_srt_ConsolidatedEntitiesAxis_547239B700B0BCD3D8E8105D9472F249" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_1B78BFEC38E56AE973C0105D94723065_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_547239B700B0BCD3D8E8105D9472F249" xlink:to="loc_srt_ConsolidatedEntitiesDomain_1B78BFEC38E56AE973C0105D94723065_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_1B78BFEC38E56AE973C0105D94723065" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_547239B700B0BCD3D8E8105D9472F249" xlink:to="loc_srt_ConsolidatedEntitiesDomain_1B78BFEC38E56AE973C0105D94723065" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_C1248358F54C60E3C8DF105D9472B080" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_1B78BFEC38E56AE973C0105D94723065" xlink:to="loc_srt_ParentCompanyMember_C1248358F54C60E3C8DF105D9472B080" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4CCD96C55D42AFD9CDC2105D9473192E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4CCD96C55D42AFD9CDC2105D9473192E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentTerm" xlink:label="loc_us-gaap_DebtInstrumentTerm_DF6FD4D79EB55E2201C4105D9473B6B3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:to="loc_us-gaap_DebtInstrumentTerm_DF6FD4D79EB55E2201C4105D9473B6B3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital" xlink:label="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_82DE0ED64BA7F94DD24B105D9473CA8D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:to="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_82DE0ED64BA7F94DD24B105D9473CA8D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProceedsFromInvestmentDistributionReturnOnInvestment" xlink:label="loc_smg_ProceedsFromInvestmentDistributionReturnOnInvestment_2F487B7AE1399B51CF1D105D9473B261" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_04B67BF2E6F06066802B105D9473313B" xlink:to="loc_smg_ProceedsFromInvestmentDistributionReturnOnInvestment_2F487B7AE1399B51CF1D105D9473B261" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsBalanceSheetDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedBalanceSheetStatementsCaptionsLineItems" xlink:label="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_AA9D48B675BA5EA48901046A934385B7" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedBalanceSheetStatementTable" xlink:label="loc_srt_CondensedBalanceSheetStatementTable_DD8EF6954015513DB0AA86745E98A628" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_AA9D48B675BA5EA48901046A934385B7" xlink:to="loc_srt_CondensedBalanceSheetStatementTable_DD8EF6954015513DB0AA86745E98A628" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_7E0EAB54815E571EB8838080E8814C1C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedBalanceSheetStatementTable_DD8EF6954015513DB0AA86745E98A628" xlink:to="loc_srt_ConsolidationItemsAxis_7E0EAB54815E571EB8838080E8814C1C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_D32F4285062A7A10EAEDC23FACF46301_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_7E0EAB54815E571EB8838080E8814C1C" xlink:to="loc_srt_ConsolidationItemsDomain_D32F4285062A7A10EAEDC23FACF46301_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_72C00E6EB9AD51D1BCC18BE3037E7A16" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_7E0EAB54815E571EB8838080E8814C1C" xlink:to="loc_srt_ConsolidationItemsDomain_72C00E6EB9AD51D1BCC18BE3037E7A16" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ReportableLegalEntitiesMember" xlink:label="loc_srt_ReportableLegalEntitiesMember_D1DDE19CBC5456E0A3144E59C4BF1512" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_72C00E6EB9AD51D1BCC18BE3037E7A16" xlink:to="loc_srt_ReportableLegalEntitiesMember_D1DDE19CBC5456E0A3144E59C4BF1512" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationEliminationsMember" xlink:label="loc_srt_ConsolidationEliminationsMember_C47EDEBDE9E15CBD8978C63CB144AC7F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_72C00E6EB9AD51D1BCC18BE3037E7A16" xlink:to="loc_srt_ConsolidationEliminationsMember_C47EDEBDE9E15CBD8978C63CB144AC7F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_3A0529E3D5E658B09D53043CC9ADDE94" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedBalanceSheetStatementTable_DD8EF6954015513DB0AA86745E98A628" xlink:to="loc_srt_ConsolidatedEntitiesAxis_3A0529E3D5E658B09D53043CC9ADDE94" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_7326C95C2AD43559BAC2C23FACF48F3A_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_3A0529E3D5E658B09D53043CC9ADDE94" xlink:to="loc_srt_ConsolidatedEntitiesDomain_7326C95C2AD43559BAC2C23FACF48F3A_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_AE2C3A813AB052D4AEADD69E4B53597E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_3A0529E3D5E658B09D53043CC9ADDE94" xlink:to="loc_srt_ConsolidatedEntitiesDomain_AE2C3A813AB052D4AEADD69E4B53597E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_ACD788E6A4E851A5858BF4F493F931AA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_AE2C3A813AB052D4AEADD69E4B53597E" xlink:to="loc_srt_ParentCompanyMember_ACD788E6A4E851A5858BF4F493F931AA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_GuarantorSubsidiariesMember" xlink:label="loc_srt_GuarantorSubsidiariesMember_250E003E1A91591C906BAB3BFF91A26F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_AE2C3A813AB052D4AEADD69E4B53597E" xlink:to="loc_srt_GuarantorSubsidiariesMember_250E003E1A91591C906BAB3BFF91A26F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_NonGuarantorSubsidiariesMember" xlink:label="loc_srt_NonGuarantorSubsidiariesMember_4C53DB95BFC15F12BBBF463F26807E97" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_AE2C3A813AB052D4AEADD69E4B53597E" xlink:to="loc_srt_NonGuarantorSubsidiariesMember_4C53DB95BFC15F12BBBF463F26807E97" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_AA9D48B675BA5EA48901046A934385B7" xlink:to="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_441AB19625C3558194EE32B57D3933EF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_441AB19625C3558194EE32B57D3933EF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_E1D251D72BD650C08C30848E46543F36" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_AccountsReceivableNetCurrent_E1D251D72BD650C08C30848E46543F36" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue" xlink:label="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_ABF08BF9D3875180962990FC4D83A302" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_PledgedAssetsSeparatelyReportedFinanceReceivablesPledgedAsCollateralAtFairValue_ABF08BF9D3875180962990FC4D83A302" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_5628AB2531CA5F109A2D3505D5DAB67A" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_InventoryNet_5628AB2531CA5F109A2D3505D5DAB67A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_89E5530A43435F5C8A0AA5891E81AEDD" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_89E5530A43435F5C8A0AA5891E81AEDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_19656E4FB8EE56719D334C71BB8A3A3E" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsCurrentAbstract_77258678AC465B44A9EF9E27D69CFAA2" xlink:to="loc_us-gaap_AssetsCurrent_19656E4FB8EE56719D334C71BB8A3A3E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityMethodInvestments" xlink:label="loc_us-gaap_EquityMethodInvestments_EBC9A60C74885E75B0F46DBA1DD2C2B1" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_EquityMethodInvestments_EBC9A60C74885E75B0F46DBA1DD2C2B1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_26C1A1344C435B9CB80C2B3970136918" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentNet_26C1A1344C435B9CB80C2B3970136918" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill_A80300DDB6235AD7A8519CDC456E6B8F" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_Goodwill_A80300DDB6235AD7A8519CDC456E6B8F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_37E204FEC4C6527A8F43DC89A122154D" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_37E204FEC4C6527A8F43DC89A122154D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_D1CF5D3B651153639488B5123C4CB220" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_D1CF5D3B651153639488B5123C4CB220" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures" xlink:label="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_34C6AE245B6B58EA85DC9455374C7E32" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures_34C6AE245B6B58EA85DC9455374C7E32" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_IntercompanyAssets" xlink:label="loc_smg_IntercompanyAssets_2A943B4ED82551BCA5D88B32CD64952A" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_smg_IntercompanyAssets_2A943B4ED82551BCA5D88B32CD64952A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_44484626E5FD59D5B3C5F55FE23F325F" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_CB1ACA5A462A548D825C3115612CC14C" xlink:to="loc_us-gaap_Assets_44484626E5FD59D5B3C5F55FE23F325F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_AA9D48B675BA5EA48901046A934385B7" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_0287FA6DE3F25781AE5D019D31A5839E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:to="loc_us-gaap_LongTermDebtCurrent_0287FA6DE3F25781AE5D019D31A5839E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_72E090BBEC9B55D6A3660A6D504A4FEE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:to="loc_us-gaap_AccountsPayableCurrent_72E090BBEC9B55D6A3660A6D504A4FEE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent_6C653FE6D9445332AC26F55726E45EED" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:to="loc_us-gaap_OtherLiabilitiesCurrent_6C653FE6D9445332AC26F55726E45EED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_609B706BB971549085615ED4A1F65743" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract_B3D4DCB1BF5552E4AD2079623CB52CBC" xlink:to="loc_us-gaap_LiabilitiesCurrent_609B706BB971549085615ED4A1F65743" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_6B5E7F8F6FC65AB69C67C4B1750BE1D6" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_6B5E7F8F6FC65AB69C67C4B1750BE1D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DueToAffiliateNoncurrent" xlink:label="loc_us-gaap_DueToAffiliateNoncurrent_57759C2EEA7250C594D5AA2BFF962BE5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_DueToAffiliateNoncurrent_57759C2EEA7250C594D5AA2BFF962BE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_08177BC2F6AB5C498F945B132A7AB645" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_OtherLiabilitiesNoncurrent_08177BC2F6AB5C498F945B132A7AB645" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets" xlink:label="loc_us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets_6DFB882340E4589A99191752231968C6" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_EquityMethodInvestmentUnderlyingEquityInNetAssets_6DFB882340E4589A99191752231968C6" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_IntercompanyLiabilities" xlink:label="loc_smg_IntercompanyLiabilities_F0081C67AED75A909EE1C37A32F0AC2C" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_smg_IntercompanyLiabilities_F0081C67AED75A909EE1C37A32F0AC2C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_D0467B4FE14A5A538C2EDF7CE42D2B70" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_Liabilities_D0467B4FE14A5A538C2EDF7CE42D2B70" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_FD3F11379959577BA00491F5F4CF0BDC" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_StockholdersEquity_FD3F11379959577BA00491F5F4CF0BDC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaap_MinorityInterest_C07FF6522EEB57A398DE3A212FA4EDFF" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_MinorityInterest_C07FF6522EEB57A398DE3A212FA4EDFF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_161F0470D12E56C1B3BC207DCF7D5B61" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_BE7A653EBF4A5F84BAB6C7439A38660A" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_161F0470D12E56C1B3BC207DCF7D5B61" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_567B18E4D83F5BE1971A9A83FA623880" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedBalanceSheetStatementsCaptionsLineItems_AA9D48B675BA5EA48901046A934385B7" xlink:to="loc_us-gaap_LiabilitiesAndStockholdersEquity_567B18E4D83F5BE1971A9A83FA623880" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsCashFlowsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedCashFlowStatementsCaptionsLineItems" xlink:label="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedCashFlowStatementTable" xlink:label="loc_srt_CondensedCashFlowStatementTable_5B4DADBCDF8B72B8CADA1646AD291CDD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_srt_CondensedCashFlowStatementTable_5B4DADBCDF8B72B8CADA1646AD291CDD" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_LegalEntityAxis" xlink:label="loc_dei_LegalEntityAxis_CE5DE58C101CDBAA92A91646AD2A3179" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedCashFlowStatementTable_5B4DADBCDF8B72B8CADA1646AD291CDD" xlink:to="loc_dei_LegalEntityAxis_CE5DE58C101CDBAA92A91646AD2A3179" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_dei_LegalEntityAxis_CE5DE58C101CDBAA92A91646AD2A3179" xlink:to="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1_default" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/dei/2019/dei-2019-01-31.xsd#dei_EntityDomain" xlink:label="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_dei_LegalEntityAxis_CE5DE58C101CDBAA92A91646AD2A3179" xlink:to="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_NonGuarantorSubsidiariesMember" xlink:label="loc_srt_NonGuarantorSubsidiariesMember_8EE76150BC7CC4A4902F1646AD2A4D91" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1" xlink:to="loc_srt_NonGuarantorSubsidiariesMember_8EE76150BC7CC4A4902F1646AD2A4D91" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_GuarantorSubsidiariesMember" xlink:label="loc_srt_GuarantorSubsidiariesMember_C94238C3E4200B8373AD1646AD2BBA32" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1" xlink:to="loc_srt_GuarantorSubsidiariesMember_C94238C3E4200B8373AD1646AD2BBA32" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_43A23162979242F33CF61646AD2B761D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_dei_EntityDomain_0B3AC848637741DB75A31646AD2AC2C1" xlink:to="loc_srt_ParentCompanyMember_43A23162979242F33CF61646AD2B761D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_A431FEBF1F5AB0AF40171646AD2C0D40" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedCashFlowStatementTable_5B4DADBCDF8B72B8CADA1646AD291CDD" xlink:to="loc_srt_ConsolidationItemsAxis_A431FEBF1F5AB0AF40171646AD2C0D40" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_A431FEBF1F5AB0AF40171646AD2C0D40" xlink:to="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_A431FEBF1F5AB0AF40171646AD2C0D40" xlink:to="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ReportableLegalEntitiesMember" xlink:label="loc_srt_ReportableLegalEntitiesMember_C60E12B8CFCC3E8DB7DC1646AD2CBBB1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA" xlink:to="loc_srt_ReportableLegalEntitiesMember_C60E12B8CFCC3E8DB7DC1646AD2CBBB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationEliminationsMember" xlink:label="loc_srt_ConsolidationEliminationsMember_2F7BDFEAE2FE566703FD1646AD2CBB6F" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_DF8E59526033423154601646AD2C6ADA" xlink:to="loc_srt_ConsolidationEliminationsMember_2F7BDFEAE2FE566703FD1646AD2CBB6F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_F011B7D3648FDF8156A51646AD2D48D6" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedCashFlowStatementTable_5B4DADBCDF8B72B8CADA1646AD291CDD" xlink:to="loc_srt_ConsolidatedEntitiesAxis_F011B7D3648FDF8156A51646AD2D48D6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_F011B7D3648FDF8156A51646AD2D48D6" xlink:to="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_F011B7D3648FDF8156A51646AD2D48D6" xlink:to="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_42AC3C4AAA28757A21BF1646AD2D071C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795" xlink:to="loc_srt_ParentCompanyMember_42AC3C4AAA28757A21BF1646AD2D071C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_GuarantorSubsidiariesMember" xlink:label="loc_srt_GuarantorSubsidiariesMember_35B7AB211336171AEE4F1646AD2D93CC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795" xlink:to="loc_srt_GuarantorSubsidiariesMember_35B7AB211336171AEE4F1646AD2D93CC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_NonGuarantorSubsidiariesMember" xlink:label="loc_srt_NonGuarantorSubsidiariesMember_EE4EBD0292C38E2A1A1C1646AD2E14C5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_242AF9DF3C3CB2D597831646AD2D5795" xlink:to="loc_srt_NonGuarantorSubsidiariesMember_EE4EBD0292C38E2A1A1C1646AD2E14C5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_1835524740E719C8E8BE1646AD2E899B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_1835524740E719C8E8BE1646AD2E899B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_880D6EECCDE4CAB6FDB21646AD2F85BA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_880D6EECCDE4CAB6FDB21646AD2F85BA" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PostClosingWorkingCapitalPaymentRelatedToDivestiture" xlink:label="loc_smg_PostClosingWorkingCapitalPaymentRelatedToDivestiture_E9115A74D70B087335261646AD2F3E07" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_smg_PostClosingWorkingCapitalPaymentRelatedToDivestiture_E9115A74D70B087335261646AD2F3E07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_BF0BA3339A961F1FBEBA1646AD2F3632" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_BF0BA3339A961F1FBEBA1646AD2F3632" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromCollectionOfLoansReceivable" xlink:label="loc_us-gaap_ProceedsFromCollectionOfLoansReceivable_2ADC26CB6005EE5AD01B1646AD2F3DFE" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_ProceedsFromCollectionOfLoansReceivable_2ADC26CB6005EE5AD01B1646AD2F3DFE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireLoansReceivable" xlink:label="loc_us-gaap_PaymentsToAcquireLoansReceivable_CE381AE7984B68691F1F1646AD2F00D5" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsToAcquireLoansReceivable_CE381AE7984B68691F1F1646AD2F00D5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates_07EF38D760E47F0550881646AD304E2B" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates_07EF38D760E47F0550881646AD304E2B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireInterestInJointVenture" xlink:label="loc_us-gaap_PaymentsToAcquireInterestInJointVenture_CE17724D7ABE7B516D0B1646AD308692" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsToAcquireInterestInJointVenture_CE17724D7ABE7B516D0B1646AD308692" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_418605AD83F037B413C11646AD30095C" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired_418605AD83F037B413C11646AD30095C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForProceedsFromOtherInvestingActivities" xlink:label="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_09BCBCB63A10C550F7771646AD30E89D" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsForProceedsFromOtherInvestingActivities_09BCBCB63A10C550F7771646AD30E89D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital" xlink:label="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_537921A3E6948BAE7D7A1646AD308AC4" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital_537921A3E6948BAE7D7A1646AD308AC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForProceedsFromBusinessesAndInterestInAffiliates" xlink:label="loc_us-gaap_PaymentsForProceedsFromBusinessesAndInterestInAffiliates_6263AFE80141B4D5F9BC1646AD31978D" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_PaymentsForProceedsFromBusinessesAndInterestInAffiliates_6263AFE80141B4D5F9BC1646AD31978D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_B0A12E56981037B305A91646AD313B79" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_662AC6F1BA18D7B9B6E51646AD2EC9BE" xlink:to="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_B0A12E56981037B305A91646AD313B79" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_C84A928C00A8074F15901646AD31924B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_C84A928C00A8074F15901646AD31924B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_41C4C04149E166B903AB1646AD319DB3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_41C4C04149E166B903AB1646AD319DB3" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsOfDividendsCommonStock" xlink:label="loc_us-gaap_PaymentsOfDividendsCommonStock_749F48902D4C67F740811646AD322EB5" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_PaymentsOfDividendsCommonStock_749F48902D4C67F740811646AD322EB5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsOfCapitalDistribution" xlink:label="loc_us-gaap_PaymentsOfCapitalDistribution_7FB7FB2BF1EC52E70B231646AD325854" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_PaymentsOfCapitalDistribution_7FB7FB2BF1EC52E70B231646AD325854" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_6FFC4BA4959DC83854C81646AD320319" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfCommonStock_6FFC4BA4959DC83854C81646AD320319" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfNotesPayable" xlink:label="loc_us-gaap_RepaymentsOfNotesPayable_EF12C609B2BD3216965E1646AD3282CD" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_RepaymentsOfNotesPayable_EF12C609B2BD3216965E1646AD3282CD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities" xlink:label="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_289EF6DA991B21263E761646AD328501" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_ExcessTaxBenefitFromShareBasedCompensationFinancingActivities_289EF6DA991B21263E761646AD328501" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromStockOptionsExercised" xlink:label="loc_us-gaap_ProceedsFromStockOptionsExercised_840A4085CC58A5ABFB141646AD32BFF7" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_ProceedsFromStockOptionsExercised_840A4085CC58A5ABFB141646AD32BFF7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsForRepurchaseOfRedeemableNoncontrollingInterest" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfRedeemableNoncontrollingInterest_50DD9B1ED33D1245896A1646AD33289E" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_PaymentsForRepurchaseOfRedeemableNoncontrollingInterest_50DD9B1ED33D1245896A1646AD33289E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PaymentsForProceedsFromIntercompanyAdvancesFromFinancingActivities" xlink:label="loc_smg_PaymentsForProceedsFromIntercompanyAdvancesFromFinancingActivities_0118A966FAA662A936781646AD33781C" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_smg_PaymentsForProceedsFromIntercompanyAdvancesFromFinancingActivities_0118A966FAA662A936781646AD33781C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_260483957C7061A7F1761646AD336D14" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_260483957C7061A7F1761646AD336D14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_PaymentsOfFinancingCosts" xlink:label="loc_us-gaap_PaymentsOfFinancingCosts_42F4367CCB0924FB4EC51646AD33EA2C" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_5E4744C09B0322774A1A1646AD3145F4" xlink:to="loc_us-gaap_PaymentsOfFinancingCosts_42F4367CCB0924FB4EC51646AD33EA2C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_BBC47DA6674216EB7B2A1646AD335297" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_BBC47DA6674216EB7B2A1646AD335297" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_4C1C845FE9A3406E88DE1646AD348AE5" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect_4C1C845FE9A3406E88DE1646AD348AE5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_670AF887BA92E4BE2E4B1646AD349626" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents_670AF887BA92E4BE2E4B1646AD349626" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4E3A745EE406F0D686ED1646AD34A4A5" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_4E3A745EE406F0D686ED1646AD34A4A5" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProceedsFromInvestmentDistributionReturnOnInvestment" xlink:label="loc_smg_ProceedsFromInvestmentDistributionReturnOnInvestment_1DE5AB2883FB9068A3071646AD347A6B" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_smg_ProceedsFromInvestmentDistributionReturnOnInvestment_1DE5AB2883FB9068A3071646AD347A6B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_3F19E641F7195A8872751646AD348383" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfSeniorLongTermDebt_3F19E641F7195A8872751646AD348383" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RepaymentsOfSeniorDebt" xlink:label="loc_us-gaap_RepaymentsOfSeniorDebt_D0734F85CF4C0EC75A861646AD35161F" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedCashFlowStatementsCaptionsLineItems_A70CDBFD029FC4D064B31646AD2EB294" xlink:to="loc_us-gaap_RepaymentsOfSeniorDebt_D0734F85CF4C0EC75A861646AD35161F" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsComprehensiveIncomeDetails" xlink:type="extended">
    <link:loc xlink:href="smg-20191228.xsd#smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems" xlink:label="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable_F98C7F7973735B858CC4C6960A4C95CC" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_StatementTable_F98C7F7973735B858CC4C6960A4C95CC" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_926FC2E51537540E9C45804482557F78" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_F98C7F7973735B858CC4C6960A4C95CC" xlink:to="loc_srt_ConsolidationItemsAxis_926FC2E51537540E9C45804482557F78" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_F3743CFEFAF01552B9D1C23FADC89708_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_926FC2E51537540E9C45804482557F78" xlink:to="loc_srt_ConsolidationItemsDomain_F3743CFEFAF01552B9D1C23FADC89708_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_6F0188307CAC54F28070B39A20F91F3F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_926FC2E51537540E9C45804482557F78" xlink:to="loc_srt_ConsolidationItemsDomain_6F0188307CAC54F28070B39A20F91F3F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ReportableLegalEntitiesMember" xlink:label="loc_srt_ReportableLegalEntitiesMember_C891900BFE895E2AB6FD402A1452A807" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_6F0188307CAC54F28070B39A20F91F3F" xlink:to="loc_srt_ReportableLegalEntitiesMember_C891900BFE895E2AB6FD402A1452A807" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationEliminationsMember" xlink:label="loc_srt_ConsolidationEliminationsMember_F2224EE84E8351828214C08759EDBC19" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_6F0188307CAC54F28070B39A20F91F3F" xlink:to="loc_srt_ConsolidationEliminationsMember_F2224EE84E8351828214C08759EDBC19" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_2D7BF39A89185D849FF2D2C9DA13D155" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_F98C7F7973735B858CC4C6960A4C95CC" xlink:to="loc_srt_ConsolidatedEntitiesAxis_2D7BF39A89185D849FF2D2C9DA13D155" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_53884799C196A4A3277FC23FADC8B299_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_2D7BF39A89185D849FF2D2C9DA13D155" xlink:to="loc_srt_ConsolidatedEntitiesDomain_53884799C196A4A3277FC23FADC8B299_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_2A325248DA7157BDB5DED2659E4E35E5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_2D7BF39A89185D849FF2D2C9DA13D155" xlink:to="loc_srt_ConsolidatedEntitiesDomain_2A325248DA7157BDB5DED2659E4E35E5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_0D31542EF2985BBB943DD105411A0568" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_2A325248DA7157BDB5DED2659E4E35E5" xlink:to="loc_srt_ParentCompanyMember_0D31542EF2985BBB943DD105411A0568" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_GuarantorSubsidiariesMember" xlink:label="loc_srt_GuarantorSubsidiariesMember_A08C047A536E53EB89641050383252ED" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_2A325248DA7157BDB5DED2659E4E35E5" xlink:to="loc_srt_GuarantorSubsidiariesMember_A08C047A536E53EB89641050383252ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_NonGuarantorSubsidiariesMember" xlink:label="loc_srt_NonGuarantorSubsidiariesMember_C4977DE2F3C15C79830813E34A8E1556" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_2A325248DA7157BDB5DED2659E4E35E5" xlink:to="loc_srt_NonGuarantorSubsidiariesMember_C4977DE2F3C15C79830813E34A8E1556" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_2A9B3D01580555418A60CB2697189DD6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_ProfitLoss_2A9B3D01580555418A60CB2697189DD6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_45174F6E6FF05B9A9AFFFB3DD12243F4" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_45174F6E6FF05B9A9AFFFB3DD12243F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_9D9EE1446C0E591FA4648F2DE8BB6B2E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_45174F6E6FF05B9A9AFFFB3DD12243F4" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax_9D9EE1446C0E591FA4648F2DE8BB6B2E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_CA6F2E2FE1255BDEB4D936514EE37C12" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_45174F6E6FF05B9A9AFFFB3DD12243F4" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossDerivativesQualifyingAsHedgesNetOfTax_CA6F2E2FE1255BDEB4D936514EE37C12" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_60F6F259937E58189E7C0DB8389466B9" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPeriodIncreaseDecreaseAbstract_45174F6E6FF05B9A9AFFFB3DD12243F4" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax_60F6F259937E58189E7C0DB8389466B9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_0CAA5FE30F8C55568DD08AE5CC3B649F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax_0CAA5FE30F8C55568DD08AE5CC3B649F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1EE8540B49F9553C9FC7ECFA8E42AFBD" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest_1EE8540B49F9553C9FC7ECFA8E42AFBD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_0954AA45FD775CACAA55B978D269E5D0" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest_0954AA45FD775CACAA55B978D269E5D0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax_64ECCD29F9885CD0B6E45A6889FBA9B6" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_ScheduleofCondensedConsolidatingStatementsofComprehensiveIncomeLossLineItems_2EFEC8E493455E8DA2BA8D5630AB5206" xlink:to="loc_us-gaap_ComprehensiveIncomeNetOfTax_64ECCD29F9885CD0B6E45A6889FBA9B6" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsStatementOfOperationsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedIncomeStatementsCaptionsLineItems" xlink:label="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_CondensedIncomeStatementTable" xlink:label="loc_srt_CondensedIncomeStatementTable_86D10123059A21F0CE2F1095EA2C80EB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_srt_CondensedIncomeStatementTable_86D10123059A21F0CE2F1095EA2C80EB" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_56713D56E2491273DFB41095EA2C6B75" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedIncomeStatementTable_86D10123059A21F0CE2F1095EA2C80EB" xlink:to="loc_srt_ConsolidationItemsAxis_56713D56E2491273DFB41095EA2C6B75" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_56713D56E2491273DFB41095EA2C6B75" xlink:to="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_56713D56E2491273DFB41095EA2C6B75" xlink:to="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ReportableLegalEntitiesMember" xlink:label="loc_srt_ReportableLegalEntitiesMember_13E7AEF38DED4FC814F01095EA2D264D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12" xlink:to="loc_srt_ReportableLegalEntitiesMember_13E7AEF38DED4FC814F01095EA2D264D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationEliminationsMember" xlink:label="loc_srt_ConsolidationEliminationsMember_EF85463BC33FCF59BAF01095EA2D0929" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_FE8480545AD6B86883701095EA2DDA12" xlink:to="loc_srt_ConsolidationEliminationsMember_EF85463BC33FCF59BAF01095EA2D0929" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesAxis" xlink:label="loc_srt_ConsolidatedEntitiesAxis_FB5DF1EB43AB474B9BFF1095EA2DB917" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_CondensedIncomeStatementTable_86D10123059A21F0CE2F1095EA2C80EB" xlink:to="loc_srt_ConsolidatedEntitiesAxis_FB5DF1EB43AB474B9BFF1095EA2DB917" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_FB5DF1EB43AB474B9BFF1095EA2DB917" xlink:to="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidatedEntitiesDomain" xlink:label="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_FB5DF1EB43AB474B9BFF1095EA2DB917" xlink:to="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ParentCompanyMember" xlink:label="loc_srt_ParentCompanyMember_45CBB3206260B29160861095EA2E55C7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37" xlink:to="loc_srt_ParentCompanyMember_45CBB3206260B29160861095EA2E55C7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_GuarantorSubsidiariesMember" xlink:label="loc_srt_GuarantorSubsidiariesMember_D381177C1A818C0AF2CA1095EA2EFACE" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37" xlink:to="loc_srt_GuarantorSubsidiariesMember_D381177C1A818C0AF2CA1095EA2EFACE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_NonGuarantorSubsidiariesMember" xlink:label="loc_srt_NonGuarantorSubsidiariesMember_451AEC4FE8D4092690D71095EA2E8B4D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_8CA83836308758B7796E1095EA2E5B37" xlink:to="loc_srt_NonGuarantorSubsidiariesMember_451AEC4FE8D4092690D71095EA2E8B4D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_3F84487C6E05356439BB1095EA2F1DAA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_3F84487C6E05356439BB1095EA2F1DAA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_5953A6C63A7719EA4B1C1095EA2F6970" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_5953A6C63A7719EA4B1C1095EA2F6970" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CostOfSalesImpairmentRestructuringAndOtherCharges" xlink:label="loc_smg_CostOfSalesImpairmentRestructuringAndOtherCharges_F777441849FCEFF6DD791095EA2F34FE" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_smg_CostOfSalesImpairmentRestructuringAndOtherCharges_F777441849FCEFF6DD791095EA2F34FE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_59E4F2DA7A9B35226A431095EA2F1FF8" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_GrossProfit_59E4F2DA7A9B35226A431095EA2F1FF8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaap_OperatingExpensesAbstract_49DFFC47C699ABDECC531095EA2F8529" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_OperatingExpensesAbstract_49DFFC47C699ABDECC531095EA2F8529" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense_4787205F53F2A6009A961095EA30C6D4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_49DFFC47C699ABDECC531095EA2F8529" xlink:to="loc_us-gaap_SellingGeneralAndAdministrativeExpense_4787205F53F2A6009A961095EA30C6D4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_E2C1A9DE149D4FEC84DD1095EA30468D" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_49DFFC47C699ABDECC531095EA2F8529" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_E2C1A9DE149D4FEC84DD1095EA30468D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherOperatingIncomeExpenseNet" xlink:label="loc_us-gaap_OtherOperatingIncomeExpenseNet_541DA3B8258030CC5E651095EA303533" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingExpensesAbstract_49DFFC47C699ABDECC531095EA2F8529" xlink:to="loc_us-gaap_OtherOperatingIncomeExpenseNet_541DA3B8258030CC5E651095EA303533" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_4E941AF24668D4626A591095EA30CBBD" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_OperatingIncomeLoss_4E941AF24668D4626A591095EA30CBBD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromSubsidiariesBeforeTax" xlink:label="loc_us-gaap_IncomeLossFromSubsidiariesBeforeTax_755283473234912AEC471095EA30263A" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeLossFromSubsidiariesBeforeTax_755283473234912AEC471095EA30263A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_581ACA65EC664B470FDA1095EA316D0F" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_581ACA65EC664B470FDA1095EA316D0F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts" xlink:label="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_8421F6FA75378BD9F3EC1095EA31E64F" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_8421F6FA75378BD9F3EC1095EA31E64F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_6246316F7F60814DD0301095EA318B5C" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_InterestExpense_6246316F7F60814DD0301095EA318B5C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_1CBAC0FD60A314DBFCAE1095EA312944" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_1CBAC0FD60A314DBFCAE1095EA312944" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_D694B1ACF20EF8468DD71095EA314CDE" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest_D694B1ACF20EF8468DD71095EA314CDE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_234066DCF3AC35807F941095EA31E070" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeTaxExpenseBenefit_234066DCF3AC35807F941095EA31E070" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_7652D2872196C23A955C1095EA321805" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest_7652D2872196C23A955C1095EA321805" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_9D5C2EB61914D86C13DC1095EA32834F" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTax_9D5C2EB61914D86C13DC1095EA32834F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss_D57FB441ED1346D24BBB1095EA32DFF2" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_ProfitLoss_D57FB441ED1346D24BBB1095EA32DFF2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_559C2F64E1CE9A56F1631095EA32ADB1" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest_559C2F64E1CE9A56F1631095EA32ADB1" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_582A09BBE662604B75C51095EA326B9F" xlink:type="locator" />
    <link:definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_CondensedIncomeStatementsCaptionsLineItems_393C46065FEDBCF79CAD1095EA2F0796" xlink:to="loc_us-gaap_NetIncomeLoss_582A09BBE662604B75C51095EA326B9F" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FinancialInformationForSubsidiaryGuarantorsAndNonGuarantorsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/ImpairmentRestructuringAndOther" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/ImpairmentRestructuringAndOtherActivityRelatedToLiabilitiesAssociatedWithRestructuringDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/ImpairmentRestructuringAndOtherAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E18840BB5B37A104807A169DE75C7AD5" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E18840BB5B37A104807A169DE75C7AD5" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_C00EFC7C9F4F236D0340169DE75CB245_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E18840BB5B37A104807A169DE75C7AD5" xlink:to="loc_us-gaap_TypeOfAdoptionMember_C00EFC7C9F4F236D0340169DE75CB245_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_C00EFC7C9F4F236D0340169DE75CB245" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_E18840BB5B37A104807A169DE75C7AD5" xlink:to="loc_us-gaap_TypeOfAdoptionMember_C00EFC7C9F4F236D0340169DE75CB245" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingStandardsUpdate201602Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201602Member_D1B9721DE55496CA75AB169DE75D66F4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_C00EFC7C9F4F236D0340169DE75CB245" xlink:to="loc_us-gaap_AccountingStandardsUpdate201602Member_D1B9721DE55496CA75AB169DE75D66F4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseAxis" xlink:label="loc_srt_LitigationCaseAxis_E3ECF8C3395BB278FF69169DE75D1B20" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:to="loc_srt_LitigationCaseAxis_E3ECF8C3395BB278FF69169DE75D1B20" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseTypeDomain" xlink:label="loc_srt_LitigationCaseTypeDomain_3AC8B09F16F3D2745F2E169DE75D3955_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_LitigationCaseAxis_E3ECF8C3395BB278FF69169DE75D1B20" xlink:to="loc_srt_LitigationCaseTypeDomain_3AC8B09F16F3D2745F2E169DE75D3955_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_LitigationCaseTypeDomain" xlink:label="loc_srt_LitigationCaseTypeDomain_3AC8B09F16F3D2745F2E169DE75D3955" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_LitigationCaseAxis_E3ECF8C3395BB278FF69169DE75D1B20" xlink:to="loc_srt_LitigationCaseTypeDomain_3AC8B09F16F3D2745F2E169DE75D3955" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_InReScottsEZSeedLitigationMember" xlink:label="loc_smg_InReScottsEZSeedLitigationMember_35AF7F544459F8F7BC04169DE75DBABA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_LitigationCaseTypeDomain_3AC8B09F16F3D2745F2E169DE75D3955" xlink:to="loc_smg_InReScottsEZSeedLitigationMember_35AF7F544459F8F7BC04169DE75DBABA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_6CE7B1DC90067307B9A7169DE75EEA57" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_6CE7B1DC90067307B9A7169DE75EEA57" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_6CE7B1DC90067307B9A7169DE75EEA57" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_6CE7B1DC90067307B9A7169DE75EEA57" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_EmployeeTerminationFacilityClosureAndImpairmentOfPropertyPlantAndEquipmentMember" xlink:label="loc_smg_EmployeeTerminationFacilityClosureAndImpairmentOfPropertyPlantAndEquipmentMember_FA2BA5E93910D8D8EBD1169DE75E0E9C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76" xlink:to="loc_smg_EmployeeTerminationFacilityClosureAndImpairmentOfPropertyPlantAndEquipmentMember_FA2BA5E93910D8D8EBD1169DE75E0E9C" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_EmployeeTerminationAndFacilityClosureMember" xlink:label="loc_smg_EmployeeTerminationAndFacilityClosureMember_1BCFB8938FDD2A307CD9169DE75FA544" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76" xlink:to="loc_smg_EmployeeTerminationAndFacilityClosureMember_1BCFB8938FDD2A307CD9169DE75FA544" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EmployeeSeveranceMember" xlink:label="loc_us-gaap_EmployeeSeveranceMember_F3702DA874D79E7E96F8169DE75F1F86" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_36B6B2DF346E4F5CBBF0169DE75EAB76" xlink:to="loc_us-gaap_EmployeeSeveranceMember_F3702DA874D79E7E96F8169DE75F1F86" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanAxis" xlink:label="loc_us-gaap_RestructuringPlanAxis_8DA381700C107A077459169DE75FFB8D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:to="loc_us-gaap_RestructuringPlanAxis_8DA381700C107A077459169DE75FFB8D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_76F1CA72F280F113A6A0169DE75F6577_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringPlanAxis_8DA381700C107A077459169DE75FFB8D" xlink:to="loc_us-gaap_RestructuringPlanDomain_76F1CA72F280F113A6A0169DE75F6577_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringPlanDomain" xlink:label="loc_us-gaap_RestructuringPlanDomain_76F1CA72F280F113A6A0169DE75F6577" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringPlanAxis_8DA381700C107A077459169DE75FFB8D" xlink:to="loc_us-gaap_RestructuringPlanDomain_76F1CA72F280F113A6A0169DE75F6577" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProjectCatalystMember" xlink:label="loc_smg_ProjectCatalystMember_959AC23065BEF893626F169DE75F08C9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringPlanDomain_76F1CA72F280F113A6A0169DE75F6577" xlink:to="loc_smg_ProjectCatalystMember_959AC23065BEF893626F169DE75F08C9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_0046A283D1701B4EB854169DE760C4A0" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_7CC8BA0E657364C64D3C169DE75C1ACA" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_0046A283D1701B4EB854169DE760C4A0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_0046A283D1701B4EB854169DE760C4A0" xlink:to="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_0046A283D1701B4EB854169DE760C4A0" xlink:to="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_HawthorneMember" xlink:label="loc_smg_HawthorneMember_0E6F7B4565ABF2D45923169DE760E6D2" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:to="loc_smg_HawthorneMember_0E6F7B4565ABF2D45923169DE760E6D2" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_U.S.ConsumerMember" xlink:label="loc_smg_U.S.ConsumerMember_925CEEB48F105AE9BE33169DE76046CF" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:to="loc_smg_U.S.ConsumerMember_925CEEB48F105AE9BE33169DE76046CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllOtherSegmentsMember" xlink:label="loc_us-gaap_AllOtherSegmentsMember_B824CA5FA6CBFF9AC405169DE761D8F6" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:to="loc_us-gaap_AllOtherSegmentsMember_B824CA5FA6CBFF9AC405169DE761D8F6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CorporateNonSegmentMember" xlink:label="loc_us-gaap_CorporateNonSegmentMember_E57C02FF5D79522F96AF169DE761F245" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_7E4DF9FFEDFDC2A96258169DE760EFD2" xlink:to="loc_us-gaap_CorporateNonSegmentMember_E57C02FF5D79522F96AF169DE761F245" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringReserve" xlink:label="loc_us-gaap_RestructuringReserve_4EA902D5068DC36B2624169DE761F91C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_RestructuringReserve_4EA902D5068DC36B2624169DE761F91C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringReserveNoncurrent" xlink:label="loc_us-gaap_RestructuringReserveNoncurrent_4DE1FC8773877ED758F0169DE761843C" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_RestructuringReserveNoncurrent_4DE1FC8773877ED758F0169DE761843C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_79988776BBD832401C28169DE762EB68" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_RestructuringCharges_79988776BBD832401C28169DE762EB68" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations" xlink:label="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_E9B4263C4259193F1FB0169DE762E231" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_E9B4263C4259193F1FB0169DE762E231" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringAndRelatedCostCostIncurredToDate1" xlink:label="loc_us-gaap_RestructuringAndRelatedCostCostIncurredToDate1_89A75C7B195373E0F25F169DE76206C3" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_RestructuringAndRelatedCostCostIncurredToDate1_89A75C7B195373E0F25F169DE76206C3" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProceedsFromSettlementOfEscrowFunds" xlink:label="loc_smg_ProceedsFromSettlementOfEscrowFunds_3547167C239DD2639463169DE762179F" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_smg_ProceedsFromSettlementOfEscrowFunds_3547167C239DD2639463169DE762179F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InsuranceRecoveries" xlink:label="loc_us-gaap_InsuranceRecoveries_1E472895EB20082454B1169DE76246DF" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_InsuranceRecoveries_1E472895EB20082454B1169DE76246DF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LossContingencyLossInPeriod" xlink:label="loc_us-gaap_LossContingencyLossInPeriod_A98A8100AF05A4C710FE169DE7621A98" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_D3BFF3B6901A3538436A169DE7610C1C" xlink:to="loc_us-gaap_LossContingencyLossInPeriod_A98A8100AF05A4C710FE169DE7621A98" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/ImpairmentRestructuringAndOtherImpairmentRestructuringAndOtherChargesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_D2F8E0AF222C47363CB2169DE76DE41D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_D2F8E0AF222C47363CB2169DE76DE41D" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCostAndReserveAxis" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_ECDBA2B695A4BD1BC308169DE76DA1EB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_D2F8E0AF222C47363CB2169DE76DE41D" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_ECDBA2B695A4BD1BC308169DE76DA1EB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_ECDBA2B695A4BD1BC308169DE76DA1EB" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfRestructuringDomain" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_ECDBA2B695A4BD1BC308169DE76DA1EB" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RestructuringAndOtherChargesMember" xlink:label="loc_smg_RestructuringAndOtherChargesMember_7FA6F98647C8A94A45DE169DE76E3EB4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A" xlink:to="loc_smg_RestructuringAndOtherChargesMember_7FA6F98647C8A94A45DE169DE76E3EB4" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PropertyPlantAndEquipmentImpairmentsMember" xlink:label="loc_smg_PropertyPlantAndEquipmentImpairmentsMember_C4C81F3E199CBB471CEE169DE76E8A4B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_27A2B1779BED8B8CD57C169DE76EDC9A" xlink:to="loc_smg_PropertyPlantAndEquipmentImpairmentsMember_C4C81F3E199CBB471CEE169DE76E8A4B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_CF085460F8ACA513F96A169DE76F1C4A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_D2F8E0AF222C47363CB2169DE76DE41D" xlink:to="loc_us-gaap_IncomeStatementLocationAxis_CF085460F8ACA513F96A169DE76F1C4A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_CF085460F8ACA513F96A169DE76F1C4A" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_CF085460F8ACA513F96A169DE76F1C4A" xlink:to="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_E8067CF13758765D05D5169DE76FC963" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8" xlink:to="loc_us-gaap_CostOfSalesMember_E8067CF13758765D05D5169DE76FC963" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingExpenseMember" xlink:label="loc_us-gaap_OperatingExpenseMember_907D67FF7C7F150BE4A5169DE76FD05A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_C4CF131AA542BB4AF63F169DE76FFFD8" xlink:to="loc_us-gaap_OperatingExpenseMember_907D67FF7C7F150BE4A5169DE76FD05A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges_24A19B636F3B7705708E16D2D43A9C14" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_us-gaap_RestructuringCharges_24A19B636F3B7705708E16D2D43A9C14" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_E23D1EC95A32C4907553169DE770B755" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_E23D1EC95A32C4907553169DE770B755" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations" xlink:label="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_82A177F3DD24D38B644C169DE770BE6C" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_82A177F3DD24D38B644C169DE770BE6C" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RestructuringAndOtherRelatedChargesDiscontinuedOperations" xlink:label="loc_smg_RestructuringAndOtherRelatedChargesDiscontinuedOperations_143949AEC0A68545710D169DE7703203" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_smg_RestructuringAndOtherRelatedChargesDiscontinuedOperations_143949AEC0A68545710D169DE7703203" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TotalImpairmentRestructuringAndOtherCharges" xlink:label="loc_smg_TotalImpairmentRestructuringAndOtherCharges_56874D456A3BE6104F49169DE770685B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_044E180C4EBF31764EB6169DE76F7397" xlink:to="loc_smg_TotalImpairmentRestructuringAndOtherCharges_56874D456A3BE6104F49169DE770685B" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/ImpairmentRestructuringAndOtherTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/IncomeTaxes" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/IncomeTaxesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxContingencyLineItems" xlink:label="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxContingencyTable" xlink:label="loc_us-gaap_IncomeTaxContingencyTable_CB6C4BB5B6F65160AA9468A8ADF04A7F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_IncomeTaxContingencyTable_CB6C4BB5B6F65160AA9468A8ADF04A7F" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_57E09EF3F2595623A599DDFBCFCC1591" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeTaxContingencyTable_CB6C4BB5B6F65160AA9468A8ADF04A7F" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_57E09EF3F2595623A599DDFBCFCC1591" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_FE7D7A16672E45078E7D49F30A247942_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_57E09EF3F2595623A599DDFBCFCC1591" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_FE7D7A16672E45078E7D49F30A247942_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_ADE2E19A44735F0088D3280A2054B97A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_57E09EF3F2595623A599DDFBCFCC1591" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_ADE2E19A44735F0088D3280A2054B97A" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DeferredTaxLiabilityMember" xlink:label="loc_smg_DeferredTaxLiabilityMember_96FB191DD8C3544CA808AA2084FA58E0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_ADE2E19A44735F0088D3280A2054B97A" xlink:to="loc_smg_DeferredTaxLiabilityMember_96FB191DD8C3544CA808AA2084FA58E0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_B07FB06C5837532DB8397FE631B11A93" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_B07FB06C5837532DB8397FE631B11A93" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxLiabilityProvisionalIncomeTaxExpenseBenefit" xlink:label="loc_smg_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxLiabilityProvisionalIncomeTaxExpenseBenefit_8968029A044251FE9E7330A24AF95419" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateDeferredTaxLiabilityProvisionalIncomeTaxExpenseBenefit_8968029A044251FE9E7330A24AF95419" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit" xlink:label="loc_smg_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit_72D272BEC5E850D09C4EDFF1B13F40F7" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_TaxCutsAndJobsActOf2017IncompleteAccountingTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit_72D272BEC5E850D09C4EDFF1B13F40F7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxReconciliationTaxCreditsForeign" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCreditsForeign_52BB8DBCF4125B058C4948B116F0A431" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_IncomeTaxReconciliationTaxCreditsForeign_52BB8DBCF4125B058C4948B116F0A431" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_D05221B385F5529FBCE323EFCDA718AC" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_D05221B385F5529FBCE323EFCDA718AC" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TaxCutsAndJobsActOf2017MeasurementPeriodAdjustmentTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit" xlink:label="loc_smg_TaxCutsAndJobsActOf2017MeasurementPeriodAdjustmentTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit_7EEEC340318F5E24B67D6D7B779D69B9" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_TaxCutsAndJobsActOf2017MeasurementPeriodAdjustmentTransitionTaxForAccumulatedForeignEarningsProvisionalIncomeTaxExpenseBenefit_7EEEC340318F5E24B67D6D7B779D69B9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_UndistributedEarningsOfForeignSubsidiaries" xlink:label="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries_D160E04FD2C157B9B19C1981D490415C" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries_D160E04FD2C157B9B19C1981D490415C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_3029CA729734592A9513D17BA9E77B51" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_3029CA729734592A9513D17BA9E77B51" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_IncreaseDecreaseInDeferredTaxLiabilities" xlink:label="loc_smg_IncreaseDecreaseInDeferredTaxLiabilities_4A9E4941D5C75801BE68414477AB1320" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_IncreaseDecreaseInDeferredTaxLiabilities_4A9E4941D5C75801BE68414477AB1320" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesDueToJointVenture" xlink:label="loc_smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesDueToJointVenture_862939C6DC37505FA29E579EE3BC0DCE" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesDueToJointVenture_862939C6DC37505FA29E579EE3BC0DCE" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesLitigationSettlement" xlink:label="loc_smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesLitigationSettlement_EBD53E92B084506BBDF4088E8CEF691D" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxContingencyLineItems_C0C7CE15428C5A0BB74E6BCB1F9C8CAF" xlink:to="loc_smg_DeferredTaxLiabilitiesReclassifiedToAccruedTaxesLitigationSettlement_EBD53E92B084506BBDF4088E8CEF691D" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/Inventories" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/InventoriesDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/InventoriesTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/InvestmentInUnconsolidatedAffiliates" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/InvestmentInUnconsolidatedAffiliatesDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_AFD143E0F9EDA9DDDB670B61D4661D90" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_8D09DF82B6962CD637B50B61D463CDF6" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_AFD143E0F9EDA9DDDB670B61D4661D90" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_8D09DF82B6962CD637B50B61D463CDF6" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_OwnershipAxis" xlink:label="loc_srt_OwnershipAxis_1AB115EE9ACB12C31CF00B61D4637FBF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_8D09DF82B6962CD637B50B61D463CDF6" xlink:to="loc_srt_OwnershipAxis_1AB115EE9ACB12C31CF00B61D4637FBF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_OwnershipDomain" xlink:label="loc_srt_OwnershipDomain_5E0C98AB55DE25546BD00B61D4647BE3_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_1AB115EE9ACB12C31CF00B61D4637FBF" xlink:to="loc_srt_OwnershipDomain_5E0C98AB55DE25546BD00B61D4647BE3_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_OwnershipDomain" xlink:label="loc_srt_OwnershipDomain_5E0C98AB55DE25546BD00B61D4647BE3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_1AB115EE9ACB12C31CF00B61D4637FBF" xlink:to="loc_srt_OwnershipDomain_5E0C98AB55DE25546BD00B61D4647BE3" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_OutdoorHomeServicesHoldingsLLCMember" xlink:label="loc_smg_OutdoorHomeServicesHoldingsLLCMember_C40DCEAFC546A108AC150B61D46484EF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_5E0C98AB55DE25546BD00B61D4647BE3" xlink:to="loc_smg_OutdoorHomeServicesHoldingsLLCMember_C40DCEAFC546A108AC150B61D46484EF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_292267271206BD3550BC0B61D464D861" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_8D09DF82B6962CD637B50B61D463CDF6" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_292267271206BD3550BC0B61D464D861" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_652D815ECE09AADF6B500B61D4641A16_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_292267271206BD3550BC0B61D464D861" xlink:to="loc_us-gaap_SegmentDomain_652D815ECE09AADF6B500B61D4641A16_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_652D815ECE09AADF6B500B61D4641A16" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_292267271206BD3550BC0B61D464D861" xlink:to="loc_us-gaap_SegmentDomain_652D815ECE09AADF6B500B61D4641A16" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_UnitedStatesConsumerSegmentMember" xlink:label="loc_smg_UnitedStatesConsumerSegmentMember_62394D098241260674880B61D4655BC4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_652D815ECE09AADF6B500B61D4641A16" xlink:to="loc_smg_UnitedStatesConsumerSegmentMember_62394D098241260674880B61D4655BC4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2FC3F594C0E54CA9354D0B61D465FF64" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_8D09DF82B6962CD637B50B61D463CDF6" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2FC3F594C0E54CA9354D0B61D465FF64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2FC3F594C0E54CA9354D0B61D465FF64" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_EquityMethodInvesteeNameDomain" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_2FC3F594C0E54CA9354D0B61D465FF64" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_TruGreenJointVentureMember" xlink:label="loc_smg_TruGreenJointVentureMember_9500975327978B931BC80B61D465CFDB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052" xlink:to="loc_smg_TruGreenJointVentureMember_9500975327978B931BC80B61D465CFDB" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_UnconsolidatedSubsidiaryWhoseProductsSupportTheProfessionalU.S.IndustrialTurfAndOrnamentalMarketMember" xlink:label="loc_smg_UnconsolidatedSubsidiaryWhoseProductsSupportTheProfessionalU.S.IndustrialTurfAndOrnamentalMarketMember_B91D2F4B98BFA76F381E0B61D466B710" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_B7B5D8B3D25C08A1FCDE0B61D465F052" xlink:to="loc_smg_UnconsolidatedSubsidiaryWhoseProductsSupportTheProfessionalU.S.IndustrialTurfAndOrnamentalMarketMember_B91D2F4B98BFA76F381E0B61D466B710" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_11ADD86B0899A3263D270B61D4662FDF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_AFD143E0F9EDA9DDDB670B61D4661D90" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_11ADD86B0899A3263D270B61D4662FDF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates_29F8944097038B940C0C0B61D466463B" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_AFD143E0F9EDA9DDDB670B61D4661D90" xlink:to="loc_us-gaap_ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates_29F8944097038B940C0C0B61D466463B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromCollectionOfAdvanceToAffiliate" xlink:label="loc_us-gaap_ProceedsFromCollectionOfAdvanceToAffiliate_F534576E2A7C9769E50A0B61D4669D0E" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_AFD143E0F9EDA9DDDB670B61D4661D90" xlink:to="loc_us-gaap_ProceedsFromCollectionOfAdvanceToAffiliate_F534576E2A7C9769E50A0B61D4669D0E" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsComponentsOfLeaseCostScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionLineItems" xlink:label="loc_us-gaap_LesseeLeaseDescriptionLineItems_95A6313CF9B3C931B0ABF7AAFF7E0913" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LesseeLeaseDescriptionTable" xlink:label="loc_us-gaap_LesseeLeaseDescriptionTable_8F83EAC43B5984D76AF3F7AAFF7D92C3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_95A6313CF9B3C931B0ABF7AAFF7E0913" xlink:to="loc_us-gaap_LesseeLeaseDescriptionTable_8F83EAC43B5984D76AF3F7AAFF7D92C3" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis_60322D966878C5C3B964F7AB12DE7254" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable_8F83EAC43B5984D76AF3F7AAFF7D92C3" xlink:to="loc_srt_RangeAxis_60322D966878C5C3B964F7AB12DE7254" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_79F7E387064674F7C979F7AB12E62B62_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_60322D966878C5C3B964F7AB12DE7254" xlink:to="loc_srt_RangeMember_79F7E387064674F7C979F7AB12E62B62_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember_79F7E387064674F7C979F7AB12E62B62" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_60322D966878C5C3B964F7AB12DE7254" xlink:to="loc_srt_RangeMember_79F7E387064674F7C979F7AB12E62B62" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember_3D23857191B83F854149F7AB2CF778AE" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_79F7E387064674F7C979F7AB12E62B62" xlink:to="loc_srt_MaximumMember_3D23857191B83F854149F7AB2CF778AE" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LesseeRemainingLeaseTerm" xlink:label="loc_smg_LesseeRemainingLeaseTerm_9E378244B212F600DFE1F7A9F1167F07" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_95A6313CF9B3C931B0ABF7AAFF7E0913" xlink:to="loc_smg_LesseeRemainingLeaseTerm_9E378244B212F600DFE1F7A9F1167F07" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ResidualValueOfLeasedAsset" xlink:label="loc_us-gaap_ResidualValueOfLeasedAsset_EEBB22A828A5059D1BD6F7AD8E096689" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems_95A6313CF9B3C931B0ABF7AAFF7E0913" xlink:to="loc_us-gaap_ResidualValueOfLeasedAsset_EEBB22A828A5059D1BD6F7AD8E096689" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsFutureMinimumAnnualOperatingAndCapitalLeasePaymentsRequiredBeforeAdoptionOfAsu842ScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsLeasesAndOtherCommitments" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsMaturitiesOfLeaseLiabilitiesByFiscalYearScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsSupplementalBalanceSheetInformationScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsSupplementalCashFlowInformationAndNonCashActivityScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/LeasesAndOtherCommitmentsWeightedAverageRemainingLeaseTermAndDiscountRateScheduleDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/MarketingAgreement" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/MarketingAgreementAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementLineItems" xlink:label="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:type="locator" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementTable" xlink:label="loc_smg_MarketingAgreementTable_81B7B5DBB78F98B3C8CD169DE73FC650" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_MarketingAgreementTable_81B7B5DBB78F98B3C8CD169DE73FC650" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis_288192F27CDF4CF9BEAA169DE73F783B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_MarketingAgreementTable_81B7B5DBB78F98B3C8CD169DE73FC650" xlink:to="loc_us-gaap_SubsequentEventTypeAxis_288192F27CDF4CF9BEAA169DE73F783B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_34FF21FA9F86BFA377E8169DE740D5DB_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_288192F27CDF4CF9BEAA169DE73F783B" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_34FF21FA9F86BFA377E8169DE740D5DB_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain_34FF21FA9F86BFA377E8169DE740D5DB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_SubsequentEventTypeAxis_288192F27CDF4CF9BEAA169DE73F783B" xlink:to="loc_us-gaap_SubsequentEventTypeDomain_34FF21FA9F86BFA377E8169DE740D5DB" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SubsequentEventMember" xlink:label="loc_us-gaap_SubsequentEventMember_4F7EE8F2F453EBEEE940169DE7408153" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SubsequentEventTypeDomain_34FF21FA9F86BFA377E8169DE740D5DB" xlink:to="loc_us-gaap_SubsequentEventMember_4F7EE8F2F453EBEEE940169DE7408153" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementAxis" xlink:label="loc_smg_MarketingAgreementAxis_4FE9215B08AA4D3AC41D169DE7414D05" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_MarketingAgreementTable_81B7B5DBB78F98B3C8CD169DE73FC650" xlink:to="loc_smg_MarketingAgreementAxis_4FE9215B08AA4D3AC41D169DE7414D05" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementDomain" xlink:label="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_smg_MarketingAgreementAxis_4FE9215B08AA4D3AC41D169DE7414D05" xlink:to="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87_default" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementDomain" xlink:label="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_smg_MarketingAgreementAxis_4FE9215B08AA4D3AC41D169DE7414D05" xlink:to="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RestatedMarketingAgreementMember" xlink:label="loc_smg_RestatedMarketingAgreementMember_4EB9DD3C4A719C36686B169DE7417CC1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87" xlink:to="loc_smg_RestatedMarketingAgreementMember_4EB9DD3C4A719C36686B169DE7417CC1" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ThirdRestatedAgreementMember" xlink:label="loc_smg_ThirdRestatedAgreementMember_BD5AF70C2838C1569430169DE74107A7" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87" xlink:to="loc_smg_ThirdRestatedAgreementMember_BD5AF70C2838C1569430169DE74107A7" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_BrandExtensionAssetPurchaseAgreementMember" xlink:label="loc_smg_BrandExtensionAssetPurchaseAgreementMember_7E45A10E91A390E78EC0169DE74108BC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_A4863CF1B385D00D5E51169DE741CD87" xlink:to="loc_smg_BrandExtensionAssetPurchaseAgreementMember_7E45A10E91A390E78EC0169DE74108BC" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionIncomeGross" xlink:label="loc_smg_CommissionIncomeGross_95E867F163C74DF0CCF7169DE742F3EB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_CommissionIncomeGross_95E867F163C74DF0CCF7169DE742F3EB" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years" xlink:label="loc_smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years_9B4141FD9B496DCE30DB169DE7422E0E" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years_9B4141FD9B496DCE30DB169DE7422E0E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MinimumTerminationFeePayableThreshold" xlink:label="loc_smg_MinimumTerminationFeePayableThreshold_77241388157121469BA9169DE7429025" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_MinimumTerminationFeePayableThreshold_77241388157121469BA9169DE7429025" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionPayablePercentageofProgramEarnings" xlink:label="loc_smg_CommissionPayablePercentageofProgramEarnings_BAE870A4A8994EAFB79C169DE7428478" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_CommissionPayablePercentageofProgramEarnings_BAE870A4A8994EAFB79C169DE7428478" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ContractualCommitmentsFutureMinimumPaymentsDue" xlink:label="loc_smg_ContractualCommitmentsFutureMinimumPaymentsDue_0B023F9E745214AC3AA0169DE743D5E8" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_ContractualCommitmentsFutureMinimumPaymentsDue_0B023F9E745214AC3AA0169DE743D5E8" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment" xlink:label="loc_smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment_01A120AD2CB3A99D50CA169DE743B253" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment_01A120AD2CB3A99D50CA169DE743B253" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes" xlink:label="loc_smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes_B81A5476F4851617DE5E169DE7432654" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes_B81A5476F4851617DE5E169DE7432654" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MinimumTerminationFeePayable" xlink:label="loc_smg_MinimumTerminationFeePayable_9FD2D737FFCDA419BFA0169DE7430F66" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_MinimumTerminationFeePayable_9FD2D737FFCDA419BFA0169DE7430F66" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_BrandDecommisioningEventPayable" xlink:label="loc_smg_BrandDecommisioningEventPayable_8E2EA3307A2A189593E2169DE7442FF9" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_BrandDecommisioningEventPayable_8E2EA3307A2A189593E2169DE7442FF9" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionThreshold" xlink:label="loc_smg_CommissionThreshold_64D2019FF05946619D25169DE744D9AE" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_CommissionThreshold_64D2019FF05946619D25169DE744D9AE" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets" xlink:label="loc_us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets_962147DFF6E8AEB35F71169DE744202C" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_us-gaap_ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets_962147DFF6E8AEB35F71169DE744202C" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PurchaseAgreementTermsConsiderationToBePaid" xlink:label="loc_smg_PurchaseAgreementTermsConsiderationToBePaid_427497F5D6DA111ABC99169DE74482D0" xlink:type="locator" />
    <link:definitionArc order="12" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_PurchaseAgreementTermsConsiderationToBePaid_427497F5D6DA111ABC99169DE74482D0" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PurchaseAgreementTermsValueOfFinishedGoodsInventory" xlink:label="loc_smg_PurchaseAgreementTermsValueOfFinishedGoodsInventory_612C15546EBE00E40D24169DE744C430" xlink:type="locator" />
    <link:definitionArc order="13" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_PurchaseAgreementTermsValueOfFinishedGoodsInventory_612C15546EBE00E40D24169DE744C430" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PurchaseAgreementTermsValueOfBrandExtensionAgreementIntangibleAsset" xlink:label="loc_smg_PurchaseAgreementTermsValueOfBrandExtensionAgreementIntangibleAsset_85F772A56E04F51DA520169DE744AF7C" xlink:type="locator" />
    <link:definitionArc order="14" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_PurchaseAgreementTermsValueOfBrandExtensionAgreementIntangibleAsset_85F772A56E04F51DA520169DE744AF7C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_86344683A451465D579A169DE744BC19" xlink:type="locator" />
    <link:definitionArc order="15" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_86344683A451465D579A169DE744BC19" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAmortizationOfDeferredCharges" xlink:label="loc_us-gaap_OtherAmortizationOfDeferredCharges_506C292D6C477B5DF57F169DE744D77D" xlink:type="locator" />
    <link:definitionArc order="16" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_us-gaap_OtherAmortizationOfDeferredCharges_506C292D6C477B5DF57F169DE744D77D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionIncomeExpenseNet" xlink:label="loc_smg_CommissionIncomeExpenseNet_40DCD2793816D0E5BBB2169DE746084D" xlink:type="locator" />
    <link:definitionArc order="17" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_CommissionIncomeExpenseNet_40DCD2793816D0E5BBB2169DE746084D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RevenuesReimbursementMarketingAgreement" xlink:label="loc_smg_RevenuesReimbursementMarketingAgreement_4D85749E9F3E5C2305A3169DE7462B0A" xlink:type="locator" />
    <link:definitionArc order="18" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_RevenuesReimbursementMarketingAgreement_4D85749E9F3E5C2305A3169DE7462B0A" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_NetSalesWithAgencyAgreement" xlink:label="loc_smg_NetSalesWithAgencyAgreement_600086AA197CBC048223169DE746598A" xlink:type="locator" />
    <link:definitionArc order="19" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_5554B84C974027D48B81169DE742E3CC" xlink:to="loc_smg_NetSalesWithAgencyAgreement_600086AA197CBC048223169DE746598A" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/MarketingAgreementNetCommissionEarnedUnderMarketingAgreementDetails" xlink:type="extended">
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementLineItems" xlink:label="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:type="locator" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementTable" xlink:label="loc_smg_MarketingAgreementTable_9305999D7E9EE52DA854F6A26EF59BF3" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_smg_MarketingAgreementTable_9305999D7E9EE52DA854F6A26EF59BF3" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementAxis" xlink:label="loc_smg_MarketingAgreementAxis_B14AAE2ECA950B43209CF6A26EF5B06E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_MarketingAgreementTable_9305999D7E9EE52DA854F6A26EF59BF3" xlink:to="loc_smg_MarketingAgreementAxis_B14AAE2ECA950B43209CF6A26EF5B06E" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementDomain" xlink:label="loc_smg_MarketingAgreementDomain_061F33FC4C1B20FAEBB0F6A26EF5C5E8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_smg_MarketingAgreementAxis_B14AAE2ECA950B43209CF6A26EF5B06E" xlink:to="loc_smg_MarketingAgreementDomain_061F33FC4C1B20FAEBB0F6A26EF5C5E8_default" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_MarketingAgreementDomain" xlink:label="loc_smg_MarketingAgreementDomain_061F33FC4C1B20FAEBB0F6A26EF5C5E8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_smg_MarketingAgreementAxis_B14AAE2ECA950B43209CF6A26EF5B06E" xlink:to="loc_smg_MarketingAgreementDomain_061F33FC4C1B20FAEBB0F6A26EF5C5E8" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RestatedMarketingAgreementMember" xlink:label="loc_smg_RestatedMarketingAgreementMember_2C5A50F4A7D655B9C548F6A26EF6321D" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_061F33FC4C1B20FAEBB0F6A26EF5C5E8" xlink:to="loc_smg_RestatedMarketingAgreementMember_2C5A50F4A7D655B9C548F6A26EF6321D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionIncomeGross" xlink:label="loc_smg_CommissionIncomeGross_923A384F695B5F3EACF9F6A26EF6F51C" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_smg_CommissionIncomeGross_923A384F695B5F3EACF9F6A26EF6F51C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_D7588BC450D58FFABFF8F6A26EF6A125" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_D7588BC450D58FFABFF8F6A26EF6A125" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherAmortizationOfDeferredCharges" xlink:label="loc_us-gaap_OtherAmortizationOfDeferredCharges_D358D35A3D550545F7C9F6A26EF7612D" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_us-gaap_OtherAmortizationOfDeferredCharges_D358D35A3D550545F7C9F6A26EF7612D" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_CommissionIncomeExpenseNet" xlink:label="loc_smg_CommissionIncomeExpenseNet_9EE76B09192E671D6A0CF6A26EF79420" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_smg_CommissionIncomeExpenseNet_9EE76B09192E671D6A0CF6A26EF79420" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RevenuesReimbursementMarketingAgreement" xlink:label="loc_smg_RevenuesReimbursementMarketingAgreement_55CDB793935588C80110F6A26EF77FF7" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_smg_RevenuesReimbursementMarketingAgreement_55CDB793935588C80110F6A26EF77FF7" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_NetSalesWithAgencyAgreement" xlink:label="loc_smg_NetSalesWithAgencyAgreement_76EF4D42BE798F214446F6A26EF754D3" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_28A6241035A542334200F6A26EF6A106" xlink:to="loc_smg_NetSalesWithAgencyAgreement_76EF4D42BE798F214446F6A26EF754D3" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/MarketingAgreementTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SegmentInformation" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SegmentInformationNetSalesByGeographicAreaDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_653E6A547C545CB08FFF16B2C227ED5C" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_88F82C9C8D5A59C696E9299F927A017E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_653E6A547C545CB08FFF16B2C227ED5C" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_88F82C9C8D5A59C696E9299F927A017E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis_83EAD1FDBCD3537D8B7FE7C836CA5724" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_88F82C9C8D5A59C696E9299F927A017E" xlink:to="loc_srt_StatementGeographicalAxis_83EAD1FDBCD3537D8B7FE7C836CA5724" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_1D175E8CD37ECA48B7CAC23FAD53207F_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_83EAD1FDBCD3537D8B7FE7C836CA5724" xlink:to="loc_srt_SegmentGeographicalDomain_1D175E8CD37ECA48B7CAC23FAD53207F_4B4AD7E4D29355C4AE3F00C0AFC3C201" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain_7CAFB6706E675AF9A736DE6B74DD755E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_83EAD1FDBCD3537D8B7FE7C836CA5724" xlink:to="loc_srt_SegmentGeographicalDomain_7CAFB6706E675AF9A736DE6B74DD755E" xlink:type="arc" />
    <link:loc xlink:href="https://xbrl.sec.gov/country/2017/country-2017-01-31.xsd#country_US" xlink:label="loc_country_US_B0EFA824D8BE56D69BCA4F710A5A79E4" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7CAFB6706E675AF9A736DE6B74DD755E" xlink:to="loc_country_US_B0EFA824D8BE56D69BCA4F710A5A79E4" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NonUsMember" xlink:label="loc_us-gaap_NonUsMember_6FB46D1E421E5FC6B2474293A2892717" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_7CAFB6706E675AF9A736DE6B74DD755E" xlink:to="loc_us-gaap_NonUsMember_6FB46D1E421E5FC6B2474293A2892717" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_C494DE9029EB5EE7B9AE594D56F88143" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_653E6A547C545CB08FFF16B2C227ED5C" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_C494DE9029EB5EE7B9AE594D56F88143" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SegmentInformationNetSalesByProductCategoryDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_E18A87B0A6F955B6678FF6A26E1906AB" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_1E2F187B9479327C6247F6A26E1628FB" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_E18A87B0A6F955B6678FF6A26E1906AB" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_1E2F187B9479327C6247F6A26E1628FB" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_51F2E816A258B12EFF73F6A26E160842" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_1E2F187B9479327C6247F6A26E1628FB" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_51F2E816A258B12EFF73F6A26E160842" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_51F2E816A258B12EFF73F6A26E160842" xlink:to="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_51F2E816A258B12EFF73F6A26E160842" xlink:to="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_U.S.ConsumerMember" xlink:label="loc_smg_U.S.ConsumerMember_78ABBC321A402E2123B7F6A26E17E080" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF" xlink:to="loc_smg_U.S.ConsumerMember_78ABBC321A402E2123B7F6A26E17E080" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_HawthorneMember" xlink:label="loc_smg_HawthorneMember_954244B635E0547545B7F6A26E17B4DC" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF" xlink:to="loc_smg_HawthorneMember_954244B635E0547545B7F6A26E17B4DC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllOtherSegmentsMember" xlink:label="loc_us-gaap_AllOtherSegmentsMember_6544F20825D6B8DF8A44F6A26E17EC64" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_4E6D6033B2D0DD2247A2F6A26E1618CF" xlink:to="loc_us-gaap_AllOtherSegmentsMember_6544F20825D6B8DF8A44F6A26E17EC64" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis_1C54730AEE9634D637CEF6A26E178BD2" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_1E2F187B9479327C6247F6A26E1628FB" xlink:to="loc_srt_ProductOrServiceAxis_1C54730AEE9634D637CEF6A26E178BD2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_1C54730AEE9634D637CEF6A26E178BD2" xlink:to="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_1C54730AEE9634D637CEF6A26E178BD2" xlink:to="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_GrowingmediaMember" xlink:label="loc_smg_GrowingmediaMember_75F4488F271E883045F3F6A26E185991" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_GrowingmediaMember_75F4488F271E883045F3F6A26E185991" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LawnCareMember" xlink:label="loc_smg_LawnCareMember_6E2D2480743E024C06F9F6A26E184774" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_LawnCareMember_6E2D2480743E024C06F9F6A26E184774" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_ControlsMember" xlink:label="loc_smg_ControlsMember_CC385FE1ECD3B606885BF6A26E186A80" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_ControlsMember_CC385FE1ECD3B606885BF6A26E186A80" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RoundupMarketingAgreementMember" xlink:label="loc_smg_RoundupMarketingAgreementMember_90DC0FFD0BA39D06535FF6A26E18BABD" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_RoundupMarketingAgreementMember_90DC0FFD0BA39D06535FF6A26E18BABD" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_IndoorUrbanAndHydroponicGardeningMember" xlink:label="loc_smg_IndoorUrbanAndHydroponicGardeningMember_DBC56A5305C0017F220DF6A26E19AA4B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_IndoorUrbanAndHydroponicGardeningMember_DBC56A5305C0017F220DF6A26E19AA4B" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_OtherProductsMember" xlink:label="loc_smg_OtherProductsMember_192DED8B80B455D7BC5DF6A26E192ACB" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_OtherProductsMember_192DED8B80B455D7BC5DF6A26E192ACB" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_OtherprimarilygardeningandcontrolsMember" xlink:label="loc_smg_OtherprimarilygardeningandcontrolsMember_161C5215E9193CC0C9F9F6A26E19C1B6" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_69506FE31DEA4DA8CCA9F6A26E17C42F" xlink:to="loc_smg_OtherprimarilygardeningandcontrolsMember_161C5215E9193CC0C9F9F6A26E19C1B6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4D0F9AE5034821002D80F6A26E19436E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_E18A87B0A6F955B6678FF6A26E1906AB" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_4D0F9AE5034821002D80F6A26E19436E" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SegmentInformationNetSalesProfitLossAndTotalAssetsBySegmentDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_B99DF80939B21A1AB4F2169DE614D5F7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_B99DF80939B21A1AB4F2169DE614D5F7" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_8BC59286643A4C83B722169DE61458CF" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_B99DF80939B21A1AB4F2169DE614D5F7" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_8BC59286643A4C83B722169DE61458CF" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_8BC59286643A4C83B722169DE61458CF" xlink:to="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_8BC59286643A4C83B722169DE61458CF" xlink:to="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_U.S.ConsumerMember" xlink:label="loc_smg_U.S.ConsumerMember_EE1AF14F66407B7101C4169DE6155D9A" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:to="loc_smg_U.S.ConsumerMember_EE1AF14F66407B7101C4169DE6155D9A" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_UnitedStatesConsumerSegmentMember" xlink:label="loc_smg_UnitedStatesConsumerSegmentMember_AED925E7635E4E6F20D4169DE61547F3" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:to="loc_smg_UnitedStatesConsumerSegmentMember_AED925E7635E4E6F20D4169DE61547F3" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_HawthorneMember" xlink:label="loc_smg_HawthorneMember_04F966AE3418B0CC21FB169DE61693EC" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:to="loc_smg_HawthorneMember_04F966AE3418B0CC21FB169DE61693EC" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AllOtherSegmentsMember" xlink:label="loc_us-gaap_AllOtherSegmentsMember_13A4259587B66A4F8188169DE6169A3D" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_E7EF5F7F907A170859E7169DE615DCC1" xlink:to="loc_us-gaap_AllOtherSegmentsMember_13A4259587B66A4F8188169DE6169A3D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementOperatingActivitiesSegmentAxis" xlink:label="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_9779415815D3E7F87351169DE61632E2" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_B99DF80939B21A1AB4F2169DE614D5F7" xlink:to="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_9779415815D3E7F87351169DE61632E2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentOperatingActivitiesDomain" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_EBB29A9BC1804FDED201169DE616A4A8_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_9779415815D3E7F87351169DE61632E2" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_EBB29A9BC1804FDED201169DE616A4A8_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentOperatingActivitiesDomain" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_EBB29A9BC1804FDED201169DE616A4A8" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_9779415815D3E7F87351169DE61632E2" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_EBB29A9BC1804FDED201169DE616A4A8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SegmentContinuingOperationsMember" xlink:label="loc_us-gaap_SegmentContinuingOperationsMember_66810C7A04178BB27217169DE6168FDD" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentOperatingActivitiesDomain_EBB29A9BC1804FDED201169DE616A4A8" xlink:to="loc_us-gaap_SegmentContinuingOperationsMember_66810C7A04178BB27217169DE6168FDD" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis_AFE51246F79DC0780B93169DE617E207" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_B99DF80939B21A1AB4F2169DE614D5F7" xlink:to="loc_srt_ConsolidationItemsAxis_AFE51246F79DC0780B93169DE617E207" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_AFE51246F79DC0780B93169DE617E207" xlink:to="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/srt/2019/elts/srt-2019-01-31.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_AFE51246F79DC0780B93169DE617E207" xlink:to="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember_5FB93C2CF3BAEBCD8184169DE6173EA9" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9" xlink:to="loc_us-gaap_OperatingSegmentsMember_5FB93C2CF3BAEBCD8184169DE6173EA9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CorporateNonSegmentMember" xlink:label="loc_us-gaap_CorporateNonSegmentMember_39324C3C8023E0E714D6169DE617287A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_8026763CFC95FA9BDA66169DE61753C9" xlink:to="loc_us-gaap_CorporateNonSegmentMember_39324C3C8023E0E714D6169DE617287A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1BB1DB7BB4C4BD93260E169DE6182141" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_1BB1DB7BB4C4BD93260E169DE6182141" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_24A846F6B0837D24892F169DE6184901" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_24A846F6B0837D24892F169DE6184901" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_98062FAB0F00EC90C27F169DE61812A6" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_98062FAB0F00EC90C27F169DE61812A6" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_B22D2B5377B383396FED169DE6197145" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_B22D2B5377B383396FED169DE6197145" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_12594B8D61F0C63F6931169DE61909BA" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_12594B8D61F0C63F6931169DE61909BA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts" xlink:label="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_3ED6D9D2D31A799841A6169DE619A8D2" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_DebtRelatedCommitmentFeesAndDebtIssuanceCosts_3ED6D9D2D31A799841A6169DE619A8D2" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_AFCE752A0C0D58A4D97A169DE6198518" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_InterestExpense_AFCE752A0C0D58A4D97A169DE6198518" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_054FF21EF22C7CC93971169DE619417C" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_054FF21EF22C7CC93971169DE619417C" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_B9109A440264D024DEE7169DE61A985D" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_C6450523FBD8D29E5059169DE618D11F" xlink:to="loc_us-gaap_AssetsAbstract_B9109A440264D024DEE7169DE61A985D" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_72BF4BFA3FB8F11F0425169DE61ADBD1" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsAbstract_B9109A440264D024DEE7169DE61A985D" xlink:to="loc_us-gaap_Assets_72BF4BFA3FB8F11F0425169DE61ADBD1" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SegmentInformationTables" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SummaryOfSignificantAccountingPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:type="locator" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable" xlink:label="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:type="arc" xbrldt:closed="true" xbrldt:contextElement="segment" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_E63E2A10BC509989C778169CDD2BCDAA" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_DebtInstrumentAxis_E63E2A10BC509989C778169CDD2BCDAA" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_E63E2A10BC509989C778169CDD2BCDAA" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_E63E2A10BC509989C778169CDD2BCDAA" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6.00PercentDue2023Member" xlink:label="loc_smg_SeniorNotes6.00PercentDue2023Member_BE92569E3B260C94597D169CDD2CB144" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88" xlink:to="loc_smg_SeniorNotes6.00PercentDue2023Member_BE92569E3B260C94597D169CDD2CB144" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SeniorNotes6625PercentDue2020Member" xlink:label="loc_smg_SeniorNotes6625PercentDue2020Member_DE208ED0516EF6CDC758169CDD2CD799" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_16D86754A45DE611A9A7169CDD2B0E88" xlink:to="loc_smg_SeniorNotes6625PercentDue2020Member_DE208ED0516EF6CDC758169CDD2CD799" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_E23BE4BB45A979F75A97169CDD2C24ED" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_E23BE4BB45A979F75A97169CDD2C24ED" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_97CBEE21EACA91B023A0169CDD2CC376_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_E23BE4BB45A979F75A97169CDD2C24ED" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_97CBEE21EACA91B023A0169CDD2CC376_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_97CBEE21EACA91B023A0169CDD2CC376" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_E23BE4BB45A979F75A97169CDD2C24ED" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_97CBEE21EACA91B023A0169CDD2CC376" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember_EF6C7EE1B93B6686302E169CDD2DB98E" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_97CBEE21EACA91B023A0169CDD2CC376" xlink:to="loc_us-gaap_SeniorNotesMember_EF6C7EE1B93B6686302E169CDD2DB98E" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsForChangeInAccountingPrincipleAxis" xlink:label="loc_us-gaap_AdjustmentsForChangeInAccountingPrincipleAxis_1299FE96395FFDB25A76169CDD2D2DD8" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_AdjustmentsForChangeInAccountingPrincipleAxis_1299FE96395FFDB25A76169CDD2D2DD8" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ChangeInAccountingPrincipleMember" xlink:label="loc_us-gaap_ChangeInAccountingPrincipleMember_AB217EF88AE66AA9EBE9169CDD2DAC99_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForChangeInAccountingPrincipleAxis_1299FE96395FFDB25A76169CDD2D2DD8" xlink:to="loc_us-gaap_ChangeInAccountingPrincipleMember_AB217EF88AE66AA9EBE9169CDD2DAC99_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_ChangeInAccountingPrincipleMember" xlink:label="loc_us-gaap_ChangeInAccountingPrincipleMember_AB217EF88AE66AA9EBE9169CDD2DAC99" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForChangeInAccountingPrincipleAxis_1299FE96395FFDB25A76169CDD2D2DD8" xlink:to="loc_us-gaap_ChangeInAccountingPrincipleMember_AB217EF88AE66AA9EBE9169CDD2DAC99" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_WeightedAverageCostingMethodToFirstInFirstOutMethodMember" xlink:label="loc_smg_WeightedAverageCostingMethodToFirstInFirstOutMethodMember_406C3A39AF7E0D117006169CDD2DD0F0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ChangeInAccountingPrincipleMember_AB217EF88AE66AA9EBE9169CDD2DAC99" xlink:to="loc_smg_WeightedAverageCostingMethodToFirstInFirstOutMethodMember_406C3A39AF7E0D117006169CDD2DD0F0" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationAxis" xlink:label="loc_us-gaap_BalanceSheetLocationAxis_63B9EFF3CC6750B11057169CDD2ED196" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_BalanceSheetLocationAxis_63B9EFF3CC6750B11057169CDD2ED196" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_63B9EFF3CC6750B11057169CDD2ED196" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BalanceSheetLocationDomain" xlink:label="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BalanceSheetLocationAxis_63B9EFF3CC6750B11057169CDD2ED196" xlink:to="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_59CD8F5EEB171B08EBE9169CDD2ED07F" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888" xlink:to="loc_us-gaap_RetainedEarningsMember_59CD8F5EEB171B08EBE9169CDD2ED07F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherCurrentLiabilitiesMember" xlink:label="loc_us-gaap_OtherCurrentLiabilitiesMember_4DD23E959F15F73CD17C169CDD2ED6E7" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888" xlink:to="loc_us-gaap_OtherCurrentLiabilitiesMember_4DD23E959F15F73CD17C169CDD2ED6E7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_OtherLiabilitiesMember" xlink:label="loc_us-gaap_OtherLiabilitiesMember_98FA795E9A26D9A8E731169CDD2F9BE9" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BalanceSheetLocationDomain_E97A9B8228CDA10F82C5169CDD2EF888" xlink:to="loc_us-gaap_OtherLiabilitiesMember_98FA795E9A26D9A8E731169CDD2F9BE9" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_68F2B18B6C667F99BDDA169CDD2F936B" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_68F2B18B6C667F99BDDA169CDD2F936B" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_68F2B18B6C667F99BDDA169CDD2F936B" xlink:to="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_68F2B18B6C667F99BDDA169CDD2F936B" xlink:to="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember_7AF9F07E1CF251B73533169CDD2FF912" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720" xlink:to="loc_us-gaap_RetainedEarningsMember_7AF9F07E1CF251B73533169CDD2FF912" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember" xlink:label="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_F5C02954A4A0DF0BF0DF169CDD2F0617" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_90D0F7744FCFC94FA6B2169CDD2F7720" xlink:to="loc_us-gaap_AociIncludingPortionAttributableToNoncontrollingInterestMember_F5C02954A4A0DF0BF0DF169CDD2F0617" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_7DAFE0F620EE3CC9CC20169CDD301216" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_7DAFE0F620EE3CC9CC20169CDD301216" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7DAFE0F620EE3CC9CC20169CDD301216" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_7DAFE0F620EE3CC9CC20169CDD301216" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_SunlightSupplyMember" xlink:label="loc_smg_SunlightSupplyMember_EE197566EE1CDEC9049D169CDD302831" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B" xlink:to="loc_smg_SunlightSupplyMember_EE197566EE1CDEC9049D169CDD302831" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_GavitaHoldingsB.V.Member" xlink:label="loc_smg_GavitaHoldingsB.V.Member_1360CEB87E249F58759A169CDD30626A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B" xlink:to="loc_smg_GavitaHoldingsB.V.Member_1360CEB87E249F58759A169CDD30626A" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_AgroluxHoldingB.V.Member" xlink:label="loc_smg_AgroluxHoldingB.V.Member_7B4E0549DE7B7515DDDF169CDD312D9F" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_EF136F666140BC1A6A88169CDD30EF5B" xlink:to="loc_smg_AgroluxHoldingB.V.Member_7B4E0549DE7B7515DDDF169CDD312D9F" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AdjustmentsForNewAccountingPronouncementsAxis" xlink:label="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_71925E9806D79C5AC7F9169CDD319951" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleTable_E93D7B06519E91CAB2EB169CDD2ABB1E" xlink:to="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_71925E9806D79C5AC7F9169CDD319951" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197_default" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_71925E9806D79C5AC7F9169CDD319951" xlink:to="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197_default" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_TypeOfAdoptionMember" xlink:label="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AdjustmentsForNewAccountingPronouncementsAxis_71925E9806D79C5AC7F9169CDD319951" xlink:to="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingStandardsUpdate201602Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201602Member_B4D5DAF62C3CC215017C169CDD31C7A7" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197" xlink:to="loc_us-gaap_AccountingStandardsUpdate201602Member_B4D5DAF62C3CC215017C169CDD31C7A7" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_AccountingStandardsUpdate201409Member" xlink:label="loc_us-gaap_AccountingStandardsUpdate201409Member_C1F132250DD231A8A518169CDD319F9A" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfAdoptionMember_83270455127A9DA55795169CDD316197" xlink:to="loc_us-gaap_AccountingStandardsUpdate201409Member_C1F132250DD231A8A518169CDD319F9A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InterestPaidNet" xlink:label="loc_us-gaap_InterestPaidNet_BE7D2B2ED3168D1265CD169CDD32FEB0" xlink:type="locator" />
    <link:definitionArc order="1" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_InterestPaidNet_BE7D2B2ED3168D1265CD169CDD32FEB0" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_PercentageOfAnnualNetSales" xlink:label="loc_smg_PercentageOfAnnualNetSales_796B5BCCBBD8FDABC2C2169CDD322D54" xlink:type="locator" />
    <link:definitionArc order="2" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_PercentageOfAnnualNetSales_796B5BCCBBD8FDABC2C2169CDD322D54" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CapitalExpendituresIncurredButNotYetPaid" xlink:label="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_EE7EDDC93AB67E273C92169CDD320D53" xlink:type="locator" />
    <link:definitionArc order="3" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_EE7EDDC93AB67E273C92169CDD320D53" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_BusinessCombinationsPostClosingWorkingCapitalAdjustmentObligation" xlink:label="loc_smg_BusinessCombinationsPostClosingWorkingCapitalAdjustmentObligation_EBB706CB5A00A4EA523F169CDD337008" xlink:type="locator" />
    <link:definitionArc order="4" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_BusinessCombinationsPostClosingWorkingCapitalAdjustmentObligation_EBB706CB5A00A4EA523F169CDD337008" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_E4D7BCBD3F48E320A4CF169CDD33F895" xlink:type="locator" />
    <link:definitionArc order="5" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_InventoryNet_E4D7BCBD3F48E320A4CF169CDD33F895" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_C68187F893C1A8F4569F169CDD33371B" xlink:type="locator" />
    <link:definitionArc order="6" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_C68187F893C1A8F4569F169CDD33371B" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_RightOfUseAsset" xlink:label="loc_smg_RightOfUseAsset_FBFF34AE129E5B08CD61169CDD33AD2C" xlink:type="locator" />
    <link:definitionArc order="7" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_RightOfUseAsset_FBFF34AE129E5B08CD61169CDD33AD2C" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LeaseLiabilityCurrent" xlink:label="loc_smg_LeaseLiabilityCurrent_7B8F44BFD48130326D17169CDD338E74" xlink:type="locator" />
    <link:definitionArc order="8" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_LeaseLiabilityCurrent_7B8F44BFD48130326D17169CDD338E74" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_LeaseLiabilityNoncurrent" xlink:label="loc_smg_LeaseLiabilityNoncurrent_637531785A770996437F169CDD33D144" xlink:type="locator" />
    <link:definitionArc order="9" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_LeaseLiabilityNoncurrent_637531785A770996437F169CDD33D144" xlink:type="arc" />
    <link:loc xlink:href="smg-20191228.xsd#smg_BondPremiumPaid" xlink:label="loc_smg_BondPremiumPaid_A961488182F005B54CA5169CDD33E47A" xlink:type="locator" />
    <link:definitionArc order="10" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_smg_BondPremiumPaid_A961488182F005B54CA5169CDD33E47A" xlink:type="arc" />
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2019/elts/us-gaap-2019-01-31.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="loc_us-gaap_IncomeTaxesPaidNet_275B4B3EA09848B1D8FA169CDD34C599" xlink:type="locator" />
    <link:definitionArc order="11" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_NewAccountingPronouncementsOrChangeInAccountingPrincipleLineItems_2D33DCD014C1C662A75F169CDD3219A4" xlink:to="loc_us-gaap_IncomeTaxesPaidNet_275B4B3EA09848B1D8FA169CDD34C599" xlink:type="arc" />
  </link:definitionLink>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesPolicies" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesSupplementalCashFlowInformationDetails" xlink:type="extended" />
  <link:definitionLink xlink:role="http://www.scotts.com/role/SummaryOfSignificantAccountingPoliciesTables" xlink:type="extended" />
</link:linkbase>
