THE COMPOSTING HANDBOOK - gnb.ca · microorganisms which live naturally in soil. They feed on a...
Transcript of THE COMPOSTING HANDBOOK - gnb.ca · microorganisms which live naturally in soil. They feed on a...
Backyard MagicTHE COMPOSTING
HANDBOOKBe eco-friendly
Backyard Magic
Table of Contents
• BackyardMagic.................................................................................................. 1 HowACompostPileWorks........................................................................... 2 UsingtheCompostYouProduce................................................................. 2
• TheCompostRecipe........................................................................................ 4
- Air.................................................................................................................... 4 - Water.............................................................................................................. 6 - Food............................................................................................................... 6 - MaterialstoUse.......................................................................................... 7 - MaterialstoAvoid...................................................................................... 7
• BuildingAHotCompostPile......................................................................... 8
• TheCompostContainer.................................................................................. 10
• OtherWaystoCompost.................................................................................. 12
- ColdComposting....................................................................................... 12 - SoilIncorporation...................................................................................... 13 - Mulching....................................................................................................... 14
• CanICompostThis?......................................................................................... 15
• 15QuestionsandAnswersaboutComposting...................................... 18
• CompostingIndoors........................................................................................ 21
• WormComposting............................................................................................ 22
• ExplorationsinComposting.......................................................................... 24
COMPOSTING 1
Backyard Magic
Is there a compost pile in your past? For most NewBrunswickers, the answer is yes. Our grandparents’
generationknewthevalueofcompostingtheiryardandkitchenwastes.Givingbacksomeofthenourishmenttheytookfromtheearthmadegoodcommonsense,anditstilldoes!
Intoday’sNewBrunswick,compostingisatraditionalideawithabroadnewappeal.It’smakingastrongcomebackinallpartsoftheProvince,aspeoplelookforpositivethingstheycandothemselvestobenefittheenvironment.Withjustalittleeffort,theresultscanbeverysatisfying.
Composting uses nature’s own recycling system. Weedsand leaves, grass clippings, vegetable peels, and variousotherorganicwastesareturnedintohumus.That’sanessentialsoilconditionerricherthananythingwecanbuy.
Whythrowawaytherawmaterialwhichgeneratessomethingsovaluable?Especiallywhencompostinghasotherbenefitsaswell.
Reducing Garbage
Upto30%ofthegarbagewethrowouteachweekcangointhecompostpile.Cuttingdomesticwastegenerationmeansalongerlifeforlandfillsitesandbetterenvironmentalmanagementfortheentirecommunity.
Helping Plants Grow
Your lawn, garden and house plants can never get too much compost. It graduallyreleasesavarietyofnutrientsjustwhenthey’rerequiredbythegrowingplants.Insectsanddiseasesdon’tseemtodoasmuchdamagewherethesoilisenrichedwithplentyofdecayedorganicmatter.Andthere’sanotherbonus:darkcompostdrawsthesun’sheattowarmthegardensoil,makingourshortgrowingseasonafewdayslonger.
Building Up the Soil
Plentyofcompostaddedtothesoilwillalsoactlikeasponge,soakingupwaterwhenitrainsandreleasingitindryspells.Itimprovesthestructureofbothsandandclaysoils,protectingthemagainstdroughtanderosion.
2 COMPOSTING
How A Compost Pile Works
Whenleavesdropfromatree,theydecayintosoftblackhumusovertime,withoutanyhelpfrompeople.Whenananimaldies,itsremainsslowlyreturntotheearth.
Anythingthatoncelivedwilleventuallydecompose.
Composting is based on this natural process and begins with the thousands ofmicroorganismswhichlivenaturallyinsoil.Theyfeedonamoistheapoforganicwastematerials,generatingconsiderableheatintheprocess.Othergroupsof“decomposer”organismsgotoworkasthetemperaturerises,anever-changingworkforceofbacteria,fungi,andinsects.
Whenthetemperaturedrops,turningorstirringthepilegivesthedecomposersmoreoxygenandtheheatbuildsagain,helpingtokillharmfulbacteria.Whenalltheeasilydecomposedmaterialhasbeenconsumed,thetemperaturedropsforthelasttimeandearthwormsandantsmaymove in,signallingthatthecompost is readytofeednewplantswithits“recycled”nutrients.
Finishedcomposthasthedistinctivefreshsmellofnewly-turnedsoiloraforestfloorinspring,andwon’theatupagainnomatterhowoftenyouturnairintothepile.Theideal result of the composting process is crumbly, dark, soil-like humus where noneoftheoriginalmaterialcanbeidentified.Thenutrientsstoredincompostdependonthe richness and variety of its ingredients, and on its exposure to harsh weather. Butexperiencedgardenersknowthereisnosuchthingasbadcompost!
Using the Compost You Produce
Finishedcompostaddsnutrientsandorganicmattertothesoil,improvingitstextureandincreasingitsabilitytoholdairandwater.Becauseitdoesn’tburnplantroots,
largequantitiesofcompostcanbeappliedtothesoilatanytime.
Soil Improvement
Try digging several centimeters (one inch) of finished compost into a flower bed orvegetablegardenbeforeplanting.Howmuchyouusewilldependonhowmuchyouhaveavailable:thesoilcanuseitall.
Youcanalsogivetrees,shrubs,andnurseryseedlingsagoodstartbyplantingtheminhalf-and-halfsoilandcompost.Newlawnswilldevelophealthyrootstokeepthemgreen,ifcompost isdug into thesoilbefore thegrassseed isapplied.Whenanestablishedlawnsufferswinter-kill,workingsomecompostintothebaldspotsbeforeseedingagainisanothergoodidea.
COMPOSTING 3
Top Dressing
Treating lawns with just over a centimeter (half-inch)ofcompostservesasaveryeffectivefeedingwhenthegroundhasdriedinthespring.Bysiftingthecompostfirst, you can remove any unattractive large pieces ormaterials that may not be fully decomposed. Theselargepiecescanbereturnedtothecompostforfurtherbreakdown.
Side Dressing
Youcanalsoapplycompostasaspotfertilizer.Scratchitlightlyintothetoplayersofsoilaroundtheplantthatneedsaboost,andwaterdeeply.
Compost “Tea”
Here’s a tidy way to supply compost nutrients to house plants or to spot-fertilizeseedlings.Soakaburlapbagoroldpillowcaseofcompost inapailofwateruntiltheliquidistea-coloured.Orstironepartcompostintothreepartswaterandpouroffthe“tea.”Usingthisliquidtowaterplantsmakesadifference,particularlyinthemiddleofthewarmgrowingseason.
Mulch
Mulchingshouldbedonelateinthespringwhenthegroundisthoroughlywarmed,butbeforesummer’sheat,toconservemoisture.Spreadapproximately8cm(3inches)ofcompostontopofthesoilaroundtreesandshrubs,fromnearthebaseofthetrunkouttothedripline.Youcanalsomulcharoundvegetablesandflowersassoonastheplantsareapproximately8cm(3inches)high,tokeeprootscoolanddiscourageweeds.
Potting Soil
House plants, window boxes and hanging baskets will all benefit from a potting soilmixed with sifted compost. Compost alone can be used for growing vegetables incontainers,andforstartingplantsfromseed.Forindooruse,youmaywanttosterilizecompostintheovenforanhourat95oC(200oF),butdon’tbealarmedbythe(temporary)strongsmell.
4 COMPOSTING
The Compost Recipe
Compostingisaverybasicprocess.Youcansimplytossgrassclippingsandleavesinaheapandletnaturedotherestinitsowngoodtime,oryoucanhelpitalong,by
providingabalanceddietforthemicro-organismswho’lldomostofthework,aswellasahomethatmeetstheirneeds.
Justlikeus,thesedecomposerorganismshavethreebasicrequirements:air,water,andfood.
Air provides oxygen and enables bacteria to carry out “aerobic” decomposition.Withoutoxygen,“anaerobic”decompositionofthewastemaytakeplaceinstead.Thisissomethingwenormallywanttoavoid,sinceanaerobicbacteriaproducetherotten-eggsmelloftenassociatedwithdecay.
Therearetwomethodsofaerobiccomposting,dependingonwhetherornotthepileheats up. A“cold” compost pile will decompose as surely as a“hot” one, but it’ll takemuchlonger.
Cold composting is slow but it’s easy. Someone with more space for compost thanphysical energy and time to devote to it may opt for the“cold” approach.This couldalso be the method to choose if your primary concernis reducing waste, rather than making quantities ofcompost.
In contrast, hot composting is a fairly fast method ofcreating compost and makes efficient use of smallerspaces. It does take more physical effort than coldcomposting,butgardenerswhowantasmuchcompostaspossiblewillusuallychoosethismethod.
There are many variations of approach, as individual asthe people who compost. You might pick one methodto start with and adapt it, as you gain experience overtime.Aboveall,keepyoursystemsimple,convenient,andsuitedtoyourlifestyle.
Air
Airpenetratesonlythetoplayersofthepile,soitneedshelptoreachthecentre.Avilesmellaroundthecomposttellsyouthatanaerobicbacteriaaremovingin,andthepilemaysimplyneedtobreathe.Inhotcomposting,plentyofairisessentialtodevelopthehightemperaturesthatkillpathogensandspeedtheprocessofdecomposition.
COMPOSTING 5
Turning
The most effective method of introducing air is to turnthepilewithagardenfork.Liftthematerialfromthetopandsides,tossitintothemoreactivecentreofthenewpile, then add the partially decomposed centre to theoutside.
Stirring
Ifyouwouldrathernotdotheworkofturningapile,trystirringitwithastickinstead;thiswon’tdistributetheairas evenly, however, so the composting process will besomewhatslower.
Aerator Tools
You can buy an aerator, a rod with flaps on one end and a handle on the other, at agardencentre.Youjabthetoolintothecompostpile,andtheflapsunfoldtoloosenthematerialsasyoupullitbackout.Theresultiseasierthanturningandproducesmoreairthanstirring.
Air Stacks
Anotherapproachistobuildyourcompostpilearoundaperforatedpipe,abundleoflongtwigs,oratubeofwiremeshstandingonend.Thiscarriesairtothecentrebetweenturnings.Withairstacks,youcanskiptheturning,althoughthepilewon’theatupasefficiently.
Elevated Compost
Mostcompostpilesrestonbareground,butyoucanbuildthepileonaraisedplatformoflooselyspacedboards,allowingairtobedrawnupfromthebottom.Ifyouelevateyourcompost,however,besuretosprinklegardensoil throughthecompostto introducethoseessentialsoilbacteria.
6 COMPOSTING
Water
Yourcompostpileshouldbeasdampasawrung-outsponge,moisttothetouch,butnowatershouldcomeoutwhenyousqueezeahandful.
Too dry?
Youcanpokeholesinthepileandwateritfromthetopwithatricklinghose.Betteryet,pullthepileapartandrebuildit,wettingeachlayerasitgoeson.Veryfibrousmaterialssuchasdeadleavesmayneedtobesoakedinabucketforanhourortwo.
Too wet?
Asoggypileshouldbeturnedsothatclumpsofmaterialarebrokenup,lettingairinandwaterout.Ifthecompostisabsolutelysoaked,youcanspreadthematerialstodryinthesun,orscatterpeatmossthroughthepileasyourebuilditwiththedriermaterialsinthecentre.
Food
Decomposer organisms work best with as varied a diet as you can feed them. Theingredients are all around us, almost anything that once lived is a candidate for thecompost,sotryforlotsofvarietytogetagoodmixoftexturesandplantnutrients.
Incompostingjargon,woodymaterialsthatarehighincarbon(autumnleaves,paper,peat moss, sawdust, cornstalks, hay and straw, etc.) are called “brown” ingredients.Materials like garden refuse, manure, tea and coffee grounds, feathers, hair, and foodscrapsarehighinnitrogen,or“green.”Somematerialscanactuallybeboth:freshgrassclippingsare“green,”forexample,butdriedgrassis“brown.”
For successful results, you can use thesimplerulethatcompostneedstobeabouthalf “brown” and half “green” by weight.Don’t bother to weigh your ingredients,though: an estimate is fine. Compostingsoonbecomesamatterofinstinct,likethecook who bakes without a recipe. If thepiledoesn’theatup,youknowthere’snotenough“green”inthemix,whileasmellofammoniameansitneedsmore“brown.”
COMPOSTING 7
Materials To Use
Green(NitrogenRich) Brown(CarbonRich)
•Algae •Buckwheathulls•Bonemeal •Coffeefilters•Coffeegrounds •Corncobs•Eggshells •Cotton/wool/silkscraps•Feathers •Grassclippings(dried)•Flowers •Hay•Fruitandfruitpeels •Leaves(dead)•Grassclippings(fresh) •Paper•Hair •Peatmoss•Manure •Pineneedles•Seaweed •Sawdust•TeaLeaves •Straw•Vegetablesandpeelings •Teabags•Weeds •Woodchips •Woodash
This list is far fromcomplete.Anythingorganiccan, in theory,becomposted -- somemoreeasilythanothers.Butcommonsensesuggestsafewexceptions.Thefollowingmaterialsmaycauseproblemsinabackyardcompostpile.
Materials To Avoid
• petwastescancontainextremely • weedswithmatureseeds,and harmfulbacteria; plantswithapersistentroot system(likecrabgrass,ground• meat,fish,fatsanddairyproducts ivy,ordaylilies),maynotbe arelikelytosmellastheyrotand killedbytheheatofthecompost; mayattractfour-footedvisitors; • leavesofrhubarbandwalnut• insect-infestedordiseasedplants containsubstancestoxicto maypersistinthecompost; insectsorotherplantssomost peoplechoosenottocompost• materialscontaminatedby them. syntheticchemicalsortreated withherbicidesorinsecticides shouldneverbeused;
8 COMPOSTING
Building A Hot Compost PileDirections
1. Gather both “green” and “brown” ingredients, enough to make a compost pilemeasuringatleast1meter(3feet)ineachdirection(high,wideandlong).
Asmallerpilewon’tgenerateorretainenoughheattoeffectivelykillanyharmfulbacteriapresent.Ifyouchoosehealthyingredientstocompost,andkeeppetsandpestsout,there’snoreasonforconcern.
Amuchlargerpileismorelikelytocompact,shuttingoutair,andismoredifficulttoworkwith.
2. Choporshredintosmallpiecesasmuchofthematerialaspossible.Drymaterialslikeleavescanberunthroughashredderorunderalawnmower.Awhipper-snipperinagarbagecanworkswelltoo,likeabigblender.
Shredded materials make a better home for decomposer organisms, with moresurfaceareaforthemtoworkon.Ashreddedpileisalsobetterinsulated,hasmorepocketsforairandretainsmoisturemoreeasily.Thefinerthepieces,thefasteryourcompostwillbefinished.
3. Layer15cm(6inches)ofwell-watered“browns”and15cmof“greens,”mixingthetwolayerstogether.
4. Alternateandmixlayersofeachtypeofmaterial,addingwaterasneeded,untilthepileisatleastonemeter(3feet)high.
Adding the material in layers simply helps you judge the right proportions of“brown” and “green.” But everything should then be thoroughly combined tocompostefficiently.
5. Coverthepiletoprotectitfromheavyrain,andwait.Thecompostshouldbegintoheatupwithinhours.
Towitnessdecompositioninaction,youcanstickametalrodintothecentreofthepileforafewminutes,thencheckifithaswarmedup.Compostthermometersareavailableatgardencentres,oryoucanmountameatthermometerattheendofastick,ifyouwantprecisetemperaturereadings.
Vapouremergingfromaerationholes,andafinegreyfungusjustunderthesurface,areothergoodsignsofanactivehotcompost.
COMPOSTING 9
What if it doesn’t heat up?
Whenacompostpilewon’theatup,theproblemisalmostcertainlyoneofthreethings:a) the pile is too small; b) it’s too dry; c) it needs more“greens” or, especially in coldweather,a“starter”togiveitmorenitrogen.
Compost Activators
Gardensupplierssellcompoststartersor“activators,”oftencomposedofhigh-nitrogenfertilizers. In some cases, “inoculants” of dehydrated bacteria are also described ascompostactivators.
While high-nitrogen fertilizers may be helpful, the benefits of adding more bacteriafrom a package have yet to be proven. All the bacteria you need should already bepresentinthesoilunderthecompostpileorthefoodandgardenwasteyouadd.Youcouldtrysoakingordinarygardensoilinwaterforanhouranddousetheheapwiththeteacolouredliquid.Butgivingaboostofnitrogentothebacteriayoualreadyhaveisthebestsolution.
Fresh stable manure is the ideal compost starter, though it may be hard for some ofustofind;harderyet toexplaintoyournext-doorneighbours.Whilethecommercialactivatorsbasedonhigh-nitrogenfertilizersdoheatupthecompostquickly,it’shardtocontroltheamountofnitrogenaddedthiswayandtheexcessmayleachoutorescapeasammoniaintotheair.
Thereareseveraleffectiveorganicalternatives:bloodmeal,finishedcompost,orwell-composted manure, for example. Or, you can simply rebuild the compost pile withadditionalgrassclippingsorother“green”materials.
The Hot Composting Timetable
Thetemperatureofthepileshouldrisesteadily,peakingbetween50oCto65oC(120oFto150oF),24hourstooneweeklater.Whenthetemperaturebeginstodrop,thecompostisreadyforturning.Breakupanyclumpsofmaterial,andmovetheoutsidepartstothebaseandcentre.Ifthepileistoodry,thisisthetimetowetit.Coverthepileagain,andwait.
Thetemperatureshouldpeakagaininaboutaweek,inapilemadeofwell-shreddedmaterials. Remember, the smaller the pieces, the faster the compost. As soon as itbeginstocool,turnthepileoncemore.Inanotherweekortwo,thecompostshouldbefinished;thatis,darkandcrumbly,fresh-smelling,withverylittleoftheoriginalmaterialidentifiable.Whencompostisreadyforuse,thetemperatureofthepilewon’triseabove43oC(110oF)nomatterhowoftenyouturnit.
10 COMPOSTING
Key Points to Remember
• Useequalamountsof“greens”and“browns.” • Mixtogetheravarietyofingredients. • Shredorchopallingredients,ifpossible. • Buildthepilelargeenoughtoretainheat. • Turnoraeratetheheapregularlytoletintheair. • Keepthepileasmoistasadampsponge.
The Compost Container
Anyonewhohascomebackhomeafteralongholidayknows that, given enough time, organic matter can
decompose even in the back of the fridge. Out in thebackyard, nature certainly doesn’t care whether thecompostisheapedoutintheopenorenclosedinabin.
However,acontainerofsomesortdoeshelptokeeptheyardneatandtheneighbourshappy.Acoveredcontaineralso means the pile can retain both heat and nutrients,whilekeepingoutrodents,raccoonsandpets.
Hotcompostpilesneedregular turning,andyou’llwanttoharvestfinishedcompostfromtimetotime.So,aboveall,thecontainershouldmakeiteasytodothiswork.Beyondthatconsideration,you’resafeinchoosingacontainerforitsappearance,convenience,cost,size,orotherqualities.
Allsortsofcompostingunitsareavailablecommercially.Some are simply“digesters,” such as a cone covering acollecting basket in a pit. Others, with solid bases, havedoorsorchutestoletyouharvestthecompostfromthebottomandputittouse.
Yourownsystemmaybeassimpleasacircleofchickenwire,orabottomlessbarrelwithairholesinitssides.Justlift itawayfromthepile,setitupagainnearby,andputthe newer layers back in, leaving behind the finishedcompost.
COMPOSTING 11
Pens
Oneofthesimpleststructures isacircleofsnowfencingorwiremeshsupportedbypostsorstakes.Atturningtime,youunwrapandremovethefencing,setitupinanewlocationnearby,andforkthecompostbackintothepen.Thisrequiresalittlemorespaceandsomeliftingeffort,anditleavesthecompostinfullview;butitisinexpensive,strongenough,andveryeasytoconstruct.
Bins
Binsaresturdierandmorediscreetthanpens.Theymayrequirealittlemoreskilltobuildbutarestill inexpensive.The foursidescanbemadeofalmostanything:wirescreenstretchedonwoodenframesoroldpalletsstandingonend.Threewallsarenormallyfixedpermanentlytogether,butmaybehinged,hookedortied.Onedesignhasthreewalls of concrete blocks, stacked without mortar, and a fourth wall of removableboards.
Toturnthepile,thefrontofthebinisremovedandthecompostforkedoutontotheground.Thenthepileisrebuiltinthebin.Youdoneedtheextragroundspaceinfrontofthebinforturning,butyoudon’thavetoliftthecompostoverawalltogetitbackin.Onevariationcallsforthebintobesetoverapit,toprovideextrainsulation.Althoughthisencouragesthepresenceofhelpfulearthworms,itdoesmeanreachingdownbelowgroundleveltoturnthecompost.
Drums
A rotating barrel composter can be made from a largedrumwithaerationholespunchedinit,andfinsinsidetoliftandmixthecompostmaterials.Ahingedloadingdoorin the side allows wastes to be added gradually. Somearerolledonthegroundtomixthecontents;othersaremountedhorizontallyonstandswithcrankattachments.Variouscommercialmodelsareavailable.
Ifbacteria is introducedwithagoodamountofgardensoil and the barrel is turned every few days, compostcanbemadeinafewweeksthiswaywithlittlephysicaleffort.
12 COMPOSTING
Boxes
Perhapsthebestsmall-scalesystemfortherelativelyen-ergeticcomposterisadesignknownastheNewZealandbox. A bottomless wooden box with ventilation spacesbetween thewall boards, its face iseasily removable tofacilitate turning. Since the compost rests directly ontheground,alidisnormallyaddedtopreventnutrientsleachingfromthepileduringheavyrains.
ANewZealandboxorsomethingsimilarcanbemadeathomewithaminimumofskill.Itcanbemovedtoanewlocationfairlyeasily,ifrequired,anditkeepsthecompostneatlyoutofsight.
Apopularvariationhastwoorthreecompartmentsinarow:compostisturnedfromoneboxintoanother;theemptiedboxthenaccumulatesthemakingsforanotherbatch.Itisidealforpeoplewhousekitchenandyardwastesastheyaccumulateandcan’tsaveupenoughmaterialstomakeareallybigpile.
Other Ways to CompostCold Composting
If you aren’t interested in the physical task of turning a compost pile, or if you haveplentyofspaceanddon’tneedthecompostinahurry,coldcompostingistheanswer.Smallhouseholdsmayaccumulateorganicwastetooslowlytobuildahotcompostpileallatonce,butyoudon’tneedmuchtostartacoldcompost.Thepilebuildsgraduallyasmaterialscometohand.
Althoughthefeedingprocessislessdemanding,theresultstakealongtime.Youcanwaitfrom6monthstoayearforabatchofcomposttobeproducedbythismethod.Itdependsonwhatgoesintothepile:soft“greens”likegrassclippingsandkitchenwastesbreakdownmuchfasterthanwoody“browns”orunshreddedpieces.Ontheplusside,absolutelynoturning is required!But it’sagood ideatobuild thepilearoundanairstack,ortopokeitwithanaeratortooloccasionally,tohelpitalong.
Aswithahotcompost,coldpilesshouldbekeptmoist,andneedavarietyoffoodsforthedecomposerorganismstoprosper.Thelowerlayersdecomposefirst,becausenewmaterialisconstantlybeingaddedtothetop.Acompostcontainerisn’tnecessary,butitmayhelpyoutogetatthefinishedstuffonthebottom.
COMPOSTING 13
Whatever you choose, a fancy container or a pile in the corner of the yard, compostproducedslowlywillneedtobecoveredoralotofitsnutrientswillbe“weatheredaway”overtime.Thismeanstheresultingmaterialwillstillbevaluableasasoilconditioner,butnotveryeffectiveasafertilizer.
Soil Incorporation
Soilincorporationisprobablythesimplestmethodofcomposting.Foodandyardwastesarefinelychopped,mixedwithsoil,andburied20cm(8inches)ordeeperintheearth.Dependingonsoiltemperature,bacterialactivity,andthecarboncontentofthewastes,decompositionwilltakefromonemonthtoayear.
Onewordofcaution,however!High-carbonmaterials(likerawautumnleaves)arenotappropriateforthismethod,becausethey’llstealtheirnitrogenfromthesurroundingsoil.Leavesmayalsoacidifythesoilorinhibitthegrowthofplantsiftheyaredugintothegroundwithoutfirstbeingatleastpartiallycomposted.
Evenhigh-nitrogenmaterialsshouldbegivenampletimetodecomposeundergroundbefore the area is used for planting, because the decomposer organisms will takenitrogenwherevertheycanfinditwhilethey’reworking.Somepeoplegetaroundtheproblemofnitrogenlossbyaddingbloodmealtothesoilbeforetheyburythecompostmaterials.
Postholing
Apostholediggerisahandytoolforsoilincorporation,althoughaspadewilldo.Theideaistodigaseriesofholesaroundthedriplineoftreesandshrubs,orinafallowareaofthegarden(toavoidstealingnitrogenfromgrowingplants),andburyorganicwastesthere.Thecompostismaderightwhereitismostneeded.Youcanusewhatspaceyouhave, thenstartoverwherethefirst loadhascomposted. If theholesaredugbeforethegroundfreezes,youcancontinuetodisposeofwastesinthiswayallthroughthewinter.
Rotation Trenching
Trenchinginvolvesdiggingalongpitinsteadofseparateholes,usuallybetweenrowsinagarden.Itiscappedwithalayerofsoilasthewastesaregraduallyadded.
This method is often used by British gardeners in a simple three-year rotation of 1)soilincorporation,2)crops,and3)pathways.Inthefirstyearatrenchisdug,filledwithnitrogen-richwastes,andcoveredwithsoil.Therownexttoitisusedtogrowcropsandathirdrowisusedasapath.
14 COMPOSTING
Ineachsuccessiveyear,thefertilesoilofthepreviousyear’strenchisusedtogrowthecrops,andtheformerpathisthecompostingtrench.Thusthegarden’ssoiliscontinuouslyrenewed.Althoughthismethoddemandsfarlessspacethanaconventionalcompostingsystem,itdoesrequirethreerowstogrowonerowofcrops.Eachgardenwillsuggestitsownvariations.Trenchescanbedugunderthepathwaysinuse,onesectionatatime,asthespaceisneeded.Inagardentoosmallforpaths,atwo-yearrotationofcropsandtrenchisfine.
Mulching
Mulchingcopiesnature’swayofcompostingonthesurfaceofthesoilandgardenershavebeendoingitforcenturies.Woody,“brown”organicmaterialsarespreadinalayerontheground,overagarden,oraroundshrubsandtrees.Becausetheyarenotdugintothesoilbutdecomposeonthesurface,theydon’tdisturbthepHbalanceofthesoilorrobitofnitrogen.
Although it is perhaps the slowest method of composting, mulching offers otherbenefits.Itdiscouragesweeds,protectssoilfromcompactingoreroding,andkeepstherootsofplantscoolandmoistinhotweather,insulatedinthewinter.
COMPOSTING 15
Can I Compost This?
Ashes Maybe Fromuntreatedwoodorpaper,yes, insmallamounts;butnotfrom barbecues,plywood,colouredor glossypaper
Banana Skins Yes Decomposerapidly;canhelpto activateaslowcompost;loadedwith plantnutrients
Cardboard Yes Shred,soak,andmixwith“greens”; buttryfirsttoreuseorrecycleit
Citrus Fruits Yes Shredrinds;buryincompostto discouragefruitflies
Coffee Grounds Yes Goodearthwormfood;usedirectly onmanyplants;compostshredded filters,too
Corn Cobs Yes Shred;addsbothfibreandnutrients tocompost;goodmulch;slowto breakdown
Dairy Products No Fatssealoffairfromcompost; odoursattractpests
Diseased Plants No Compostheatmaynotdestroy disease;destroyordiscardtoavoid spreading
Dishwater Maybe Ifwaterdoesn’tcontaingreaseor chemicalcleansers,useittowetpile
Dust and Lint Maybe Usevacuumcleanerdebrisandlint fromclothesdryer,ifmostlynatural fibres
Eggshells Yes Dryandcrushfirst;goodearthworm food;slowtobreakdown;help neutralizeacidity;asmulch,may discourageslugs
16 COMPOSTING
Evergreen Needles Maybe Highlyacidic;betteryet,useas mulch
Fabrics Maybe Smallscrapsofwool,cotton,feltand silk;notsyntheticfibresorblends
Feathers Yes Keepsomewhatwetterthanusual; extremelyhighinnitrogen
Fish Maybe Odoursandpestsareproblemswith freshorsmokedfish,butdried fishmealisfine
Grass Clippings Yes Availableandvaluable;mixwellto avoidclumps;leavesomeclippings tofeedlawn
Hair Yes Bothhumanandpethair;keepquite damp;avoidusingifcolouredwith chemicals
Hay and Straw Yes Verygoodfibre,nutrientsusuallylow
Leaves Yes Shredandsoak;addbothnutrients andfibre;tendtobeslightlyacidic
Manure Yes Cow,horse,pig,rabbit,poultry,the fresherthebetter,helpsanycompost
Meat and Bones No Odoursandpestsareproblems;but dried,groundbonemealisfine sourceofnitrogen
Soil Yes Addsdecomposersoilorganisms; scatterlightlythroughpiletoavoid compacting
Nutshells Maybe Crushdelicateshellslikepeanuts; heaviershellsarebetterusedas decorativemulch
Paper Maybe Shred;notglossy/colouredwhich containchemicals;bettertorecycle ifpossible
COMPOSTING 17
Pet Wastes No Riskofpathogensandparasites; useonlybarnyardmanure(horse, cow,sheep,etc.)
Rhubarb Maybe Rawleavespoisonoustohumans; compostedleavesmayharminsects andotherplants;stemsarefine; rootsmaycontinuetogrow
Sawdust Maybe Hardwoodsawdust,yes,invery smallquantities;softwoodsmay inhibitcomposting;plywoodmay containchemicals
Seafood Shells Yes Crushorgrindveryfinely;break downveryslowly;reduceacidity; goodmulch
Seaweed Yes Rinseoffsaltsoitwon’tcontaminate soil;greatfertilizer
Sod Yes Knockoffexcesssoil;pileupside down;covertopreventrooting; compostseparatelytoavoid compaction
Soup Maybe Vegetable,yes;donotusesoups withcreamormeat-basedbrothsto avoidodoursandpests;readlabels oncannedsoups.
Tea Leaves Yes Highinnitrogen;canbeapplied directlytosomeplants;composttea bagstoo
Toadstools Yes Decomposequickly;excellent sourceofmanyminerals
Weeds Yes Discardmatureseeds,persistent roots,weedstreatedwithherbicides/ pesticides
Wood Chips Yes Shredifpossibleandsoak;usebig piecesasmulchfirst,compostwhen weathered
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15 Questions and Answers About CompostingStructure/Space:
Do I need a bin to make compost?
No,organicmatterwilleventuallydecomposewithouthumanhelp.Butacontainerofsomesortwillkeepyourpileneat,protectitfromtheweatherandpests,andmakethejoboftendingitmucheasier.
Where is the best place to put a compost pile?
Pickashelteredspot,outofthefullsummersunifpossible.Avoidtreesandshrubsthatmaypushtheirrootsupintothepile.Andgivesomethoughttobothconvenienceandappearanceinchoosingalocation.
Process/Problems:
What is the “easiest” way to compost yard wastes and food wastes?
Woodyor“brown”yardwastes,liketreetrimmingsandautumnleaves,canbeshreddedandusedasmulcharoundplantsandonpaths.Eventuallythey’llreturntothesoil.Foodwastes,aswellasgreenyardwasteslikevegetabletopsandgrassclippings,canbedugintotheground.Uselarger-scale“soilincorporation”onlywhereyouwon’tbeplantingforafewmonths.
Can I compost in the winter?
EvenresearchteamsontheSouthPolehavecompostedtheir garbage successfully! You can retain heat a littlelongerinthefallbycoveringthepileandinsulatingthecontainer, perhaps with bags of leaves. Increasing theamountof“green”orusingacompostactivatormayhelpkeepthetemperatureup.Keepaddingtothecompostthroughthewinter:itmaynotseemtobedoingmuch,butthefrozenmaterialswillquicklyfinishbreakingdownwhenspringcomes.
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What if the pile has an odour?
Anearthyscentisnormalandinoffensive,butawell-builtcompostshouldn’tproduceunpleasantodours.If itdoes,yourproblemiseithertoomuch“green”stuff(ammoniasmell)ortoolittleair(rotten-eggsmell).First,aeratethepile.Iftheodourpersists,turnandrebuildthepilewithmore“brown”materials.
Should I wear gloves to handle compost?
Ifyouhaven’tcompostedpetmanures,whichcontainbacteriaharmfultohumans,thereisnoneedtoweargloves.Finishedcompostcanbehandledjustasyouwouldgardensoil.
How can kitchen wastes be stored for later composting?
Collectfoodscrapsinaplasticcontainerinthefridgeorfreezer, ifyouhavespace,orkeep a tightly lidded container handy, covering each addition of compostable foodwasteswithjustenoughpeatmossorsawdusttocontrolodours.
Should I add ground limestone, soil, or fertilizer?
Aperfectlygoodcompostpilecanbebuiltoutofnothingfancierthanleavesandgrassclippings. Lime will balance out the pH of a pile of highly acidic materials, like pineneedles.However,mostcompostisnaturallyclosetoneutralinpHbythetimeitisreadyforuse.Ascatteringofsoilshouldbeaddedifyourcompost isn’t incontactwiththeground,becauseitisthesoilorganismsthatdothedecomposingwork.Withavarietyofingredients,fertilizerisseldomnecessary.
What if the compost pile doesn’t heat up?
Theoddsarethatan inactivecompostpile justdoesn’thaveenough“greens” in it tostartitstemperaturerising.Theansweristorebuildthepilewithmorehigh-nitrogenmaterialsora“starter”likemanure“tea.”Thatwillprobablysolvetheproblem,butalsocheckthatthepileisasmoistasawrung-outsponge.
How do I compost with too many high-nitrogen materials?
Youcandigextra“greens”directlyintothesoil,storesomeinafreezerorsealedcontainer,buypeatmosstomixwith it,or,asa lastresort,drysomeinthesuntodecreasethenitrogencontent.Perhapsacompostingneighbourcanuseadonation?
20 COMPOSTING
How do I compost with too many high-carbon materials?
Thisisoftenaprobleminautumn,whenthere’snoshortageofdeadleaves.Ifyouhavespace,bagsomeandstorethemforcoveringupthefoodscrapsyou’lladdthroughthewinter,orforspringandsummerwhen“browns”arehardertofind.Bagsofleavesalsomake insulatingwindbreaks forcompostbins.Ormoistenthe leavesandstore theminsealedbagstobegindecomposing. Inspring,addthemtothecompost.Mulchingisanotheralternative,butshredtheleavesfinelyandagain,acompostingneighbourmightbeabletouseyoursurplus.
Finished Compost:
When is compost “finished” and safe to use?
When an active compost pile fails to heatuponcemore,andverylittleoftheoriginalmaterial can be recognized (perhaps aneggshell or the shapes of old leaves), thecompost is ready to use. It will be therich brown colour of good soil and smellsomethinglikethehumusofaforestfloor.
Does it need to be sterilized or screened?
Compostdoesn’tneedtobesterilizedorscreened for thegarden.Foruse indoors, itshouldbeputthroughastrainerorquarter-inchscreenandsterilizedintheovenfor1hourat95oC(200oF).Youwillprobablywanttoscreenthecompostyouusetotopdressthelawnaswell.
Do I need to fertilize if I use compost?
Thenutritionalvalueofcompostdependsonthematerialsthatwereusedtomakeit.That’swhyit’simportanttoputasmuchvarietyintothepileaspossible.Ifyou’retryingtoenrichaseverelydepletedgardenplot,orgrowingplantslikepeoniesthatdemandalotoffood,youmightwanttoaddsomecommerciallyproducedorganicfertilizer.Soiltestingisagoodideainthiscase.Formostgardensandflowerbeds,however,compostprovidesaconcentratedsourceofbalancednutrientsaswellastheorganicmatterthesoilneedstostorethem.
What if I make too much compost?
It’shardtoimaginesuchasituation!Theearthcanusealltheorganicmatteryoucangiveit,andyoucanapplycompostatanytimeofyear.Digitintoflowerbeds,layeritover
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avegetablegarden,orspreaditunderatreetofeedtheroots.Finelyscreenedcompostcanbescatteredoveralawn,orsterilizedandmixedwithpottingsoilforhouseplants.Andyoucanstorecompostinabagorholdingpen,aslongasitiswellprotectedfromrain,windandsun.
Composting IndoorsNobackyardorgarden?Collectyourkitchenwasteinthefreezeroracoveredpailtogivetoacompostingfriend.Ormakeyourowncompostindoors!
Holding Units
With a basement, garage, porch or balcony, you haveplentyofspaceforacoldcompostingcontainer.
Tryalargemetalorplasticgarbagecanwithalid.Punchnailholesinthesidesandtop,andstirwithabroomhandleoruseanaeratorstacktogetoxygenintothecompost.Startyourcompostwitha“brown”layer:approximately8cm(3inches)ofpeatmoss,sawdust,orshreddedleavesfromsomeoneelse’sfallclean-up.
Collect your kitchen scraps into a covered pail as theycomealong.Everyfewdays,whenthepailfillsup,justtossthecontentsontothecompostandcovereachadditionwitha littlemore“brown”stufftocontrolodours.Addafewhandfulsoftopsoilifyoucangetit,orcompostfromanearlierbatch,andkeepallthematerialsasmoistasawrung-outsponge.
Harvestingthecompostiseasiestwithtwocansonthego.Oncethefirstcanisfilled,juststiriteveryfewdaysandkeepitmoist.Newkitchenscrapsgointothesecondcan.Bythetimeitisfull,thefirstbatchshouldbereadyforuse.
Bags-and-Pails
Evenwithoutthespacetohidelargecontainers,orthephysicalabilitytostirthecontents,you can still compost anaerobically (without oxygen). Composting this way takes sixmonthsorayear,butitrequiresverylittleeffort,justsomestoragespace.
Collectkitchenscrapsinacoveredpailandsprinklesawdustorcrumbledpeatmossovereachadditiontoit.Orstorefoodwastes(clearlylabelled)inthefridgeorfreezer.When
22 COMPOSTING
the pail is full, empty it into a sturdy plastic bag without holes and add just enoughwatertomoistenitthoroughly.
Half-filleachbagandsealitverytightly.Tobeonthesafeside,youmaywanttoputitinsideasecondbag.Don’tbetemptedtopeekuntilit’shadtimetofinishcomposting:decomposerorganismsworkingwithoutairproduceanawfulsmell!
Storethebagsoutofyourway,onabalconywhentheweatheriswarm,orinastoragecloset. The compost is ready to use when you open a bag and it doesn’t smell ofdecompositiononcetheairfrominsidehasdispersed.
Worm Composting
Letwormsdothework!Compostingwithearthworms,or“vermi-composting,”isgreatforapartmentdwellerswhodon’thaveyardspace,andforhomeownerswhodon’t
wanttohikethroughsnowdriftstoabackyardcompostbin.Andmanykidslovekeepinghundredsofwigglersforpets.ThereareseveralcompaniesinCanada,whocansellyouthebins,bedding,wormsandall.
Covered Bin
Yourwormscanliveinaplasticbinorwoodenbox,withplentyofairholespunchedinthesidesandtop.Linethewormbinwithnylonnettokeepthesmallonesin.Holesinthebottomareneededfordrainage,soyou’llwantatrayunderthebin.Somepeoplemovetheirwormsouttoabalconyoryardinwarmseasons.Youmayfinditmoreconvenienttohaveseveralsmaller,moreportableunitsratherthanonelargeone.Thesizeoftheboxwillalsodependonhowmuchspaceyouhave.
Bedding
Loamorblacktopsoil,availablefromgardencentres,makesaparticularlygoodbeddingmaterial.Beddingcanalsobeshreddednewspapers,soakedtosoftentheedges(thewormswilleatthistoo,soavoidcolouredinksandglossypaper)oramixtureofsawdust,peat,shreddedleaves,andsoil.
Fill the bin with about 30 cm (1 foot) of bedding, about as damp as a wrung-outsponge,notsoggyandnotdry.Withalidonthebinandregularfeedingoftheworms,maintainingthecorrectmoisturelevelshouldn’tbedifficult.
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Worms
It’s true that earthworms aren’t pets for the squeamish, but they are great littlecomposters!You’ll want the kind of worms that are sold for fishing bait, such as redwigglers or brandling worms, not ordinary field worms from someone’s garden.Redwormsnormallyliveinbarnyardmanurepiles,andfeedonfreshorganicmaterial.Fieldwormsarebetteratdigestingthingsthatarealreadywelldecomposedandaren’tlikelytosurviveinawormbinonadietofkitchenscraps.
Yourvaluablelittleredwormswilllivequietlyintheirdarkboxandmultiplyrapidly.Justbury your leftovers in their bedding after each meal. It is unlikely that you will havetoo much waste to compost: redworms will eat their own weight in kitchen scrapsand bedding each day. The castings they produce are incredibly rich fertilizer andlooklikefine-texturedsoil.Foreachcubicfootofwormbin,planonusing200grams(approximatelyhalfapound)ofredwigglers(about500,dependingontheirsize).
Food
Coffeegrounds,vegetablesandfruitaretherecommendedfoodforworms.Avarieddietisimportant.Avoidbones,dairyproducts,meats,garlicandpotatopeelings.Whatdoesn’tcauseodoursorattractinsectswillsimplytakeaverylongtimetobreakdown.Eggshellsareessentialtokeepthebeddingfrombecomingtooacidicfortheworms.Drythemwell,crushthem,andsprinklethetinypiecesoverthetopofthebedding.
Temperature
Redwormswillsurviveintemperaturesfrom5oCto32oC(40oFto90oF)butpreferitatoraboveroomtemperature.Ifyoukeepthewormbinoutsideingoodweather,bereadytobringitinpromptlywhenthetemperaturedrops.
Harvesting the Castings
Removing the worm-compost couldn’t be easier.You will notice that redworms hatethelight.They’llwriggledownintotheirbeddingwheneveryoutakethelidoffthebin.Every few months, when the castings outweigh the bedding that remains, place theopenedbinunderaverybrightlightandgivethewormstenminutestogetwellawayfromthesurface.Thenthecoastisclearforscrapingawaythewormcastingsfromthetoplayer.
Whenyoustarttoseethewormsagain,keepthelightonthemandgivethemanothertenminutestogodeeperstill.Andremovethenextlayerofcompost.Keepgoinginthiswayuntiltheharvestisdone.Thenfillupthebinwithfreshbeddingandstartagain.
24 COMPOSTING
Outdoors
Somepeoplebuildspecialwormpitstotakeadvantageoftheworms’naturaltalents.Tomakeawormpit,allyouhavetodoisdigasquarehole60cm(2feet)deepandsetabottomlessboxoverit.Thecompostmaterialsandwormsaretossedinhere.Youcankeepaddingorganicwasteasitaccumulates.
Keepthepiledampanddark,andthewormswilldotherest.Remembertoharvestyourcompostcarefully,inbrightsunshine,tosavethewormsfromanunpleasantfate.Theywon’tlivelongifthey’restrandedinordinarygardensoil,dumpedtherewithaforkfulofcompost.
Here inNewBrunswick,ourclimate istooextremeforredwormstosurviveoutdoorsthroughthewinter.Someworm-ownersinmilderareashavegoodluckusingverydeepwormpitswiththickly insulatedwalls,but it’s riskybusiness indeed.Better,bringthewormsindoorstoabinassoonasarealfrostthreatens.
Explorations in Composting
For teachers, youth group leaders, or day-care supervisors, here are some simpleexperimentswhichwillhelpyourkidsunderstandhowcompostinghelpstheearth
andplants.Youwon’tneedmuchinthewayofequipment,andtheresultsarefuntowatch.
How does compost help growing plants?
Activity
1. Soaksixoreightbeansovernightinwater.
2. Fill one jar or flowerpot with ordinary soil dug up from your garden, lawn, orpathway.
3. Fillasecondjarorpotwiththesamekindofsoil,butmixithalf-and-halfwithfinishedcompost.Ifyoudon’thaveacompostpileyet,youcanusecompostedmanurefromagardencentre.
4. Plantafewbeansineachpot.
5. Placethemwheretheywillbewarmandhavesomesunshine.
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6. Keepthepotswatered,andcheckeachdaytoseewhathappens.
Soilsthatcontainlotsofdecomposedorganicmatter,likecompost,canstoremorefood for the plants and release it to them as they need it. Unless you are luckyenoughtohaveveryrichsoilalready,you’llprobablyfindthatthebeansgrewfasterandstrongerinthepotthathadcompostaddedtothesoil.
How does compost help soil structure?
Activity
1. Findtwowide-mouthedglasscontainers(mayonnaisejarsareperfect).
2. Maketwosmallbasketsorwireracksofquarter-inchscreen.Foreachrackyouwillneedapieceofscreenabout7.5cmby25cm(3inchesby10inches).Bendthewiresothatitfitsdownintothejarslikealittlebasket.
3. Findaplacewherethesoilisverylightincolour,likeaconstructionsiteoraheavilyfarmedfield.Collectseveralclumpsofsoilaboutthesizeofafist.
4. Collectasecondsampleofsoilclumpsfromdarkearth,suchasagardenthathasbeenfedregularlywithcompost,orapark.
5. Fillthejarswithwaterwithin2.5cm(oneinch)ofthetop.
6. Placethelumpsofsoil inthebasketsandlowerthemgently intothejars.Watchclosely!
Whydoesthesoilinonebasketfallapartanddroptothebottomofthejar?Organicmatter, like decomposed leaves and roots, helps soil hold water and air. Whenorganic matter is used up, we have to give nature time to replace it, or feed theearthwithcompost.Whenearthholdstogetherlikethis,itcanstandthehardrainsthatwashawaylesshealthysoil.
26 COMPOSTING
Can everything be turned into compost?
Activity
1. Find four or five wide-mouthedglassjars.You’llwanttobeabletoseethroughthesidesofthem.
2. Collectabananaskinorapplecore, a scrap of newspaper, aleaf(greenorbrown),andapieceofplastic.Theremaybeotherthingsyouwanttotestaswell.
3. Placeeachoftheseitemsinaseparatejar.Holdthemclosetotheside,whereyoucanseethem,andfillthejarswithordinarysoil.
4. Don’tcoverthejars,butmakesurethesoilcoversyoursamples.
5. Watereveryday,justenoughtokeepthesoildamp.Don’tletitdryoutorfreeze.
6. Watchwhathappens,ordoesn’thappen,ineachjar.
You’ll soonnoticechanges insomeofyoursamplesas theystart todecompose.Some change faster than others, and the piece of plastic won’t change at all!Anythingthatoncecamefromalivingthingiscalled“organic”andwillbreakdown.Youcanusethesetomakecompost.Whatdoyouthinkhappenstoallthesethingswhenthey’retakenawaybythegarbagecollectorandburiedinalandfill?
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Other Experiments to TryThe Garbageless Lunch
Knowingwhatwillbreakdowninacompostpileandwhatwon’t,trytopackyourselfalunchthatwon’tleavegarbagebehind.Willachocolatebarmakegarbage?Abanana?Shouldyouchoosewaxedpaperoraplasticbagforwrappingyoursandwich?Here’ssomethingtrickytothinkabout:isitbettertouseapapernapkin,eventhoughitwilldecompose,oraclothnapkinthatyoucanwashanduseagaintomorrow?Whatwillyoucarryyourlunchin?
Taking Out the Trash
Thisweek,countthenumberofgarbagebagsyourfamilyfills.Maybesomeonewillhelpyouweighthem.Writedownwhatyoudiscover.
Wasthisanordinaryweek?Figureouthowmuchgarbageyou’dhaveafterayear.Wheredoesthegarbagego,andwhathappenstoit?Whatdoyouthinkmighthappenwhenthere’snomorespaceforourgarbage?
Nextweek,collectalltheorganicgarbageinaseparatepailorbag.Itwillstartsmellingbeforetheendoftheweek,sokeepthecontainerclosedwhenyouaren’tfillingit.Attheendoftheweek,countandweightheregulargarbagebagsthatyourfamilyhasfilled.Comparetheresultstolastweek’sgarbage.Isthereadifference?
Notes
Department of Environment
P.O.Box6000Fredericton,NewBrunswick
Canada
Telephone:(506)453-3700Fax:(506)453-3676
Email:[email protected]
www.gnb.ca/environment
Reprintedin2010
ThankyoutotheFrederictonBackyardCompostersforprovidingsomephotographs.
The Short Course in Composting
Withnothingfancierthanfallenleavesandgrassclippings,youcanmaketherichdarkhumusthattheearthneeds
tosupportgrowingplants.Andcompostingorganicwastescanreducebymorethanathirdtheamountofgarbageproducedbyyourhousehold.
Compostcanbemade inas littleastwoweeks,or itcantakeasmuchasayear,dependingontheeffortandattentionyouwant to give to the process. Most organic materials, choppedorshreddedintosmallpieces,willdecomposequicklyifthey’rekept moist and turned or stirred regularly to expose them toair.
Organic wastes will break down into humus even without acompostcontainer.Butsomesortofbarrel,boxorpenwillkeepyourbackyardcompostpiletidyanddiscourageanimalpests.
Indoorsorout,anyonecancompost.Andalmostanythingthatoncelivedisacandidateforcomposting.Someorganicwastesaretrouble-makerstoavoid,however.Althoughactivecompostpiles build up temperatures high enough to kill many weedsandharmfulbacteria,meatandfish,bones,dairyproductsandfats,petwastes,diseasedplantmaterials,andthoseweedswithhardyrootsorripeseedsshouldnotbecomposted.