BESTPRACTICES

It is the mission of Stream Team to protect and enhance water resources and associated habitats and wildlife in Thurston County through citizen action and education. Stream Team is funded and jointly managed by the stormwater utilities of the Cities of Lacey, Olympia and Tumwater and Thurston County. www.streamteam.info

Generalconsiderations• Sheetmulchingisatechniquetoconvertanareaoflawnorweedstoaperennialnativeplantingbed.Itisaneasy,lowinputmethodbecauseitinvolvesminimaldiggingandtheexistingplantmaterialdoesnotneedtoberemoved.

• Sheetmulchworksbycuttingofflightfromgrassandweedssotheyeventuallydieanddecompose.Theareawillbereadytoplantapproximatelythreetosixmonthsafterapplicationofthesheet-mulch.

• Decomposedvegetationandothermaterialsusedinsheetmulchbuildsoilhealthandfertility,whichwillhelpnativeplantsestablishquicker,growfaster,andneedlesswater.

• Whenapplyingsheetmulch,itisimportanttoavoidgapsortearsthroughwhichweedscangrow.Avoidwalkingonsheetmulchwhileitisdecomposing,whichcancausetears.Toreducegaps,usethelargestpiecesofcardboardyoucanfind.

• Sheetmulchworksbestonrelativelyevenground.Ifcardboardcannotbelaidflat,weedsarelikelytogrowthroughit.

• Toaiddecomposition,isbesttoapplysheetmulchinwinterorspringwhenthesoiliswet.Ifapplyinginsummer,wetthesoilthoroughlybeforelayingdowncardboard/newspaper.

• Sheetmulchcanbeusedtoconverttheentirelawnareaortocreatebedsinanexistinglawn.Bededgingcanbeusedtocreateacleanerlookandreducemaintenance.Choosewideredgingmadefromadurablematerialsuchasconcreteorrecycledrubber.Thinplasticedgingwillflopoveranddoesnotoffergoodresults.

• Sheetmulchcanbeusedaroundexistingplants.Removegrassandothervegetationinaone-footwideringaroundeachplant.Leaveasix-inchgapbetweenthebaseoftheplantandthecardboard.

• Measureworkareatocalculatetheamountofwoodchipmulchyouneed. – 1Volumeofwoodchipmulchforthreeinchcoverage(incubicyards)=(workareaX0.25)/27

ToolsandMaterials• Cardboardwithalltape,plastic,andstaplesremoved• Compost,lawnclippings,manure,orotherweed-freefineorganicmaterial,ifneededtoamendpoorsoil(Optional)

• WoodChipMulchorStraw• BedEdging(Optional)• Shovel• Rake• Wheelbarrow• GardenHoseorFlour

SheetMulching

BESTPRACTICES:SheetMulching 2of2

It is the mission of Stream Team to protect and enhance water resources and associated habitats and wildlife in Thurston County through citizen action and education. Stream Team is funded and jointly managed by the stormwater utilities of the Cities of Lacey, Olympia and Tumwater and Thurston County. www.streamteam.info

ApplicationMethod• Useagardenhoseoralineofflourtotracetheedgeoftheareayouaresheetmulching.(Figure1)• Usingashovel,removegrassorweedsinastripalongtheedgeofthearea.Thiswillpreventgrassfromspreadingintothebedonceitisplanted.Thestripshouldbethewidthofthebededging,orsixincheswideifnoedgingwillbeused.(Figure2and3)

• Ifworkinginsummer,wetthegroundwellwithagardenhoseorsprinkler.• Installthebededging,ifusing.

• Applycardboard,compostandwoodchipmulchoverthearea.– Flatteneachboxandlayitdownsothattherearetwolayersofcardboardovertheentirearea.Overlaptheedgesbysixinches.

– Toavoiddamagingordisruptingthecardboard,minimizethenumberoftripswiththewheelbarrowoverthecardboard.

– Laythecardboarddowninsectionsstartingatthefarcornerofthearea.

– Applyonetotwoinchesofcompost,ifusing,andthreeinchesofmulchtoeachsection before movingontothenext.

– Repeat,workingoutwardstocovertheentireareaasifyou werepaintingafloor.

– Tomakespreadingcompostandchipseasier,dumpmany smallpilesfromthewheelbarrowratherthanafewlargepiles.

– Coverthegrass-freestripwithcardboardsothattheouteredgeofthecardboardisinlinewiththeouteredgeofthestrip.(Figure4and5)

Appendix2.Source:OlyWild.Allphotos:GregRabourn

Figure1:Tracetheedgeofthearea.

Figure2:Removegrassinastripattheedge.

Figure3:Removegrassinastripattheedge.

Figure4:Covergrass-freestripwithcardboard.

Figure5:Finishedsheetmulch.