Home CompostingHome Composting

A project of the Virginia Cooperative A project of the Virginia Cooperative Extension Master GardenersExtension Master Gardeners

What is compost?What is compost?

Stable humus materialStable humus material Produced when organic Produced when organic

matter is broken down by matter is broken down by bacteria and fungibacteria and fungi

Valuable soil amendmentValuable soil amendment Pleasant smelling, “black Pleasant smelling, “black

gold”gold” Nature’s way of Nature’s way of

recycling!recycling!

All organic matter will decompose in due time. All organic matter will decompose in due time. (Gardeners just like to help it along…) (Gardeners just like to help it along…)

Why you should compostWhy you should compost Improves tilth of soilImproves tilth of soil Protects and promotes health of your soil & plantsProtects and promotes health of your soil & plants May reduce need for fertilizersMay reduce need for fertilizers Saves you $$$ on soil amendmentsSaves you $$$ on soil amendments Keeps yard waste out of the landfillKeeps yard waste out of the landfill

What should you compost?What should you compost?

From your yardFrom your yard LeavesLeaves Grass clippingsGrass clippings Weeds (pest and disease-free, no seeds)Weeds (pest and disease-free, no seeds) Trimmings and pulled annuals (see above)Trimmings and pulled annuals (see above) Small diameter twigsSmall diameter twigs

What might you compost?What might you compost?

From your kitchenFrom your kitchen EggshellsEggshells Fruit and vegetable peelingsFruit and vegetable peelings Halloween pumpkinsHalloween pumpkins Crushed crab or lobster shellsCrushed crab or lobster shells Flower arrangementsFlower arrangements

What What elseelse can you compost? can you compost?

From your neighborhood businessesFrom your neighborhood businesses

Coffee groundsCoffee grounds Tea bagsTea bags Hops and other brewery wasteHops and other brewery waste Horse manure and beddingHorse manure and bedding

What you should What you should nevernever compost compost Noxious weeds (poison ivy, Noxious weeds (poison ivy,

invasive plants…)invasive plants…) Dog and cat feces, or cat litterDog and cat feces, or cat litter Large diameter woody branchesLarge diameter woody branches ““Glossy” leavesGlossy” leavesAlso:Also:

Insect-ridden plants Insect-ridden plants Plants that have gone to seedPlants that have gone to seed Dairy products, meat, oils, or Dairy products, meat, oils, or

greasegrease

Oh, RATS!Oh, RATS! If you have a local “rodent If you have a local “rodent

problem”, don’t put food problem”, don’t put food scraps in your compost at allscraps in your compost at all

There’s no such thing as a There’s no such thing as a rat-proof bin!rat-proof bin!

How do you make compost?How do you make compost?

To speed up the natural decomposition of organic To speed up the natural decomposition of organic matter, you can regulate:matter, you can regulate:

1.1. MoistureMoisture

2.2. TemperatureTemperature

3.3. AirAir

4.4. Mix of ingredientsMix of ingredients

MoistureMoisture Water, in the right quantity, is needed for Water, in the right quantity, is needed for

breakdown to occurbreakdown to occur Most sources describe the right moisture Most sources describe the right moisture

level as damp, like a wrung-out spongelevel as damp, like a wrung-out sponge Leave compost open to the rainLeave compost open to the rain Consider adding waste water, if Consider adding waste water, if

necessary from necessary from a birdbatha birdbath an aquarium or pondan aquarium or pond pot used to steam or boil vegetablespot used to steam or boil vegetables

TemperatureTemperature

““Hot” piles are simply piles with high metabolic Hot” piles are simply piles with high metabolic activity (= faster breakdown)activity (= faster breakdown)

““Cold” piles will do the job, just more slowlyCold” piles will do the job, just more slowly

To maintain a “hot” pileTo maintain a “hot” pile

Pile must be > 27 cubic feet and Pile must be > 27 cubic feet and < 125 cubic feet, a.k.a. a pile 3-5 < 125 cubic feet, a.k.a. a pile 3-5 feet high, wide and deep (ideal is feet high, wide and deep (ideal is approx. 4’x4’x4’)approx. 4’x4’x4’)

For best results, shred materials For best results, shred materials to increase surface area for to increase surface area for microbes to workmicrobes to work

Turn the pile – inside to outside – Turn the pile – inside to outside – every two weeks or when the every two weeks or when the temp reaches 130-140 degreestemp reaches 130-140 degrees

AirAir

Anaerobic conditions may result fromAnaerobic conditions may result from Tightly packed material, like grass clippingsTightly packed material, like grass clippings Failure to turn pileFailure to turn pile No coarse materialNo coarse material Pile in close contact with ground (hint: a wooden Pile in close contact with ground (hint: a wooden

pallet is worth it’s weight in compost!) pallet is worth it’s weight in compost!) Microbes cannot survive under Microbes cannot survive under

anaerobic conditionsanaerobic conditions Too much moisture = too little air!Too much moisture = too little air!

Mix of ingredientsMix of ingredients To layer or not to layer…To layer or not to layer… Greens and Browns, does it Greens and Browns, does it

matter?matter? Greens are nitrogen-rich Greens are nitrogen-rich

materialsmaterials Fresh grass clippingsFresh grass clippings Vegetable scrapsVegetable scraps Fresh hay, weeds and plant Fresh hay, weeds and plant

wastewaste Browns are carbon-rich Browns are carbon-rich

materialsmaterials LeavesLeaves Sawdust (from untreated Sawdust (from untreated

wood)wood) Wood chipsWood chips StrawStraw

What you What you don’tdon’t need need to make compostto make compost

Special equipmentSpecial equipment BioactivatorsBioactivators WormsWorms SoilSoil

LimeLime YeastYeast Finished compostFinished compost

or Fertilizer!or Fertilizer!

What type of pile?What type of pile?

Troubleshooting ITroubleshooting I

My pile smells like ammoniaMy pile smells like ammonia mix in dry brownsmix in dry browns

My pile smells like rotten eggsMy pile smells like rotten eggs Aerate, add dry browns to pile if it is too wetAerate, add dry browns to pile if it is too wet

My pile isn’t heating upMy pile isn’t heating up Check for proper moisture content, air spaces, Check for proper moisture content, air spaces,

pile size, nitrogen (greens)pile size, nitrogen (greens) My pile is TOO hotMy pile is TOO hot

Turn the pileTurn the pile

Troubleshooting IITroubleshooting II

My pile is attracting ratsMy pile is attracting rats Don’t add food scraps, or bury them deeplyDon’t add food scraps, or bury them deeply

My pile isn’t active at allMy pile isn’t active at all Check moisture throughoutCheck moisture throughout Add nitrogen (grass clippings, coffee grounds…) Add nitrogen (grass clippings, coffee grounds…) Shred material if possibleShred material if possible

Is it done yet???Is it done yet???

Proper composting takes time!Proper composting takes time! Finished compost is earthy smelling, dark, and Finished compost is earthy smelling, dark, and

crumblycrumbly Finished compost will stay at or near the air Finished compost will stay at or near the air

temperature temperature Expect hot piles to take several months; cold Expect hot piles to take several months; cold

piles will take a year or more piles will take a year or more

Using your compostUsing your compost Flower and vegetable gardens Flower and vegetable gardens

Mix 3 to 4 inches of compost through Mix 3 to 4 inches of compost through entire bed before plantingentire bed before planting

Top dress established plants with Top dress established plants with several inches compostseveral inches compost

MulchMulch To eliminate weeds, protect soil, and To eliminate weeds, protect soil, and

keep roots moistkeep roots moist Seeding new lawns Seeding new lawns

Till in 4 inches of compostTill in 4 inches of compost Enriching established lawnsEnriching established lawns

Rake an inch or so of compost over Rake an inch or so of compost over lawn in falllawn in fall

Your soil Your soil thanks you thanks you for coming!for coming!

Prepared by Master Gardeners Mary Jane Ross and Sue Williams, 2005