What is Composting?
• Composting is a method of treating solid
waste by using microorganisms ability to break
• The broken down material can be reapplied to
the environment – “brown gold” is like natural
fertilizer that your plants will LOVE!
• Americans generate about 210 million tons of
trash each year!
• Most of that (about 57%) is dumped in landfills.
• Another 27% is recycled – think paper, plastic,
glass and metals
• What about the rest?
How do you set up a Compost bin?
• Good composting creates an ideal
environment for microorganisms to break
down or cause decay in organic matter
– soil (or another source of microorganisms)
– Organic waste – newspaper, leaves, grass, kitchen
waste, woody shrubs, etc.
How do the Microorganisms work?
• Microorganisms consume the organic waste
and break it down into simple parts
• This creates humus
• No, not the stuff you eat.
• Humus is the dark brown or black layer that
contains the broken down organic matter
PLUS inorganic nutrients like nitrogen,
phosphorus and potassium.
You mean there’s a food-web in
• A compost pile is actually a complex
organization of living things.
• Bacteria and fungi break down the organic
matter – single celled protozoa, small worms
and mites feed on the bacteria and fungi –
predatory invertebrates (millipedes, beetles,
etc.) feed on the protozoa, mites and worms.
Choose a Site
• Make sure your compost pile is discretely away
from your house, but not so far that you don’t
use it or help to maintain it!
• Other things to consider:
– Can your neighbors see your compost pile?
– Downwind – even good piles smell at times
– Sunlight – too much dries it out, but some will help to
warm the pile
– Drainage – good drainage is key to keeping the pile
from becoming water logged
– Base – bare earth is better than concrete
Choose a Structure
• Depends on your yard
and how active you’re
going to be in your
• Make sure the structure
is ventilated to allow
more oxygen to reach
– Fruit and vegetable wastes -
peels, skins, seeds, leaves
– Egg shells
– Coffee grounds (including
paper filters), tea bags, used
– Corncobs - should be
shredded to make them break
– Grass clippings - Some grass is
okay, but too much will add excess
nitrogen to the compost pile and
make it smell bad. It may be best
to use a mulching lawn mower for
– Pine needles
– Woody materials (branches, twigs)
– Straw or hay
Newspapers, sawdust & sea weed (just in case you have some around the house)
DO NOT ADD THESE:
• Human waste or pet litter - They carry diseases and parasites, as
well as cause an unpleasant odor.
• Diseased garden plants - They can infect the compost pile and
influence the finished product.
• Invasive weeds - Spores and seeds of invasive weeds (buttercups,
morning glory, quack grass) can survive the decomposition process
and spread to your desired plants when you use the finished
• Charcoal ashes - They are toxic to the soil microorganisms.
• Glossy paper - The inks are toxic to the soil microorganisms.
• Pesticide-treated plant material - These are harmful to the
compost food-web organisms, and pesticides may survive into the
Care and Feeding
• Turning the compost frequently allows the
microorganisms to get adequate oxygen
• Finished compost settles to the bottom because of it’s
– When is it done?
• Finished compost does not smell bad – it smells
like earth or peat moss
• It is warm – the microorganisms release heat as
they break down the organic matter
• Gas bubbles are ok – it’s just CO2 being released
from the microorganisms
• Improve the soil structure in your garden or yard
• Increase the activity of soil microbes
• Enhance the nutrients of your soil
• Improve the chemistry of your soil, particularly the
degree of acidity (pH)
• Insulate the changes in soil temperature around plants
• Improve insect/disease resistance in your garden plants
• Decrease the amount of waste you send off to a
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