1. Put different yard trimmings such as leaves and grass clippings in a bin or pile.  You should have a mix of green material (grass clippings, kitchen scraps, weeds, green leaves) and brown material (brown dry leaves, dried grass, straw, shredded cornstalks). 

2. Add water so the heap is slightly damp. 
   
   
3. "Turn" or "mix" the heap at least once a month.  You'll maximize your composting efforts if you continuously turn or mix the heap.  Mixing your heap will help to keep the browns and greens in balance, will distribute moisture, and add essential air (oxygen) to the mixture.  The core (the inside) of the compost heap is always hotter and is the center of activity.  The outside is generally less active and much cooler.  To increase the efficiency of the composting process, mix the heap to bring more of the raw materials from the outside to the core.  The pile should reach a temperature of 130 to 160 degrees and will be ready in 6 to 9 months.
   
   
4. Add compost material, such as fruit and vegetable scraps, as generated.  Cover the new kitchen scraps with leaves or bury them in a heap.  If the heap dries out, add more water to keep it damp.
   
   
5. After 12 to 16 months, most of the material at the bottom of the heap will be dark, rich sweet-smelling compost.  Sift or sort out any large, un-decomposed materials. Sprinkle on your yard and garden.

What can be composted:

What should be avoided:

Red worms can be used to turn kitchen scraps into compost.  This method of composting generally doesn’t take as long but a proper balance is still required to maintain optimum conditions.  The following items are needed for a worm bin: worms, box, food, and bin contents.  They are described below.

Worms:

There are two red worms that can adapt to a box environment: Lumbricus rebellus and Eisinia foetida.  Other worms are not suitable for the living conditions.  Given that conditions are very rarely ideal, assume that two pounds of worms are need for each pound of scraps generated per day.

Box:

The box size can vary, depending upon the average amount of scraps produced during the week.  A box 1'x2'x3' can handle about 6 pounds per week.  The box should have air holes to allow oxygen in and carbon dioxide out.  The box should be covered to keep moisture in and light out. 

Place the bin in a shady area that stays between 55°F to 77°F, preferably, but definitely above 50°F and below 85°F. 

Box contents:

Put bedding in the bin.  Bedding is soaked and wrung out shredded strips of corrugated cardboard and newspapers.  Strips should be about 4” long and 1” wide.  Add a handful of topsoil to provide some grit so the worms can break down the food.

Worms need about 75% to 95% moisture in their surroundings.  Check the moisture of your bedding by squeezing some in your hand.  If more than 5 drops are produced, the bedding is too moist and you should add some dry bedding to the mixture.

Food:

Fruit, vegetables, tea, coffee grounds, crushed egg shells, and bread can be put in the bin.  Avoid pet litter, vegetable oils, meats, fats, dairy products and non-biodegradable materials.  Bury your scraps in a different location each time. 

Harvesting:

When the compost appears to the dark crumbly mixture, push the compost into one side of the bin.  Fill the empty side with new bedding and begin to bury food scraps there.  When the worms have no food left in the old pile, they’ll move into the new bedding and you can harvest the compost.

Adapted from `Washington State Compost Educator’s Guide’ produced by Washington State University and Department of Ecology with funding from EPA Region 10.

Links:

www.seattletilth.org
www.cityfarmer.org/wormcomp61.html