How to make compost

Composting puts Mother Nature on a fast track by quickening thenatural process of decomposition. Microscopic organisms break downyard and kitchen waste, and manure, into a rich organic fertilizerand soil amendment. When finished, compost nutrients -- primarilynitrogen, phosphate and potassium -- are in a form that can bereadily used by plants.

Essential elements: Successful composting depends on air, waterand heat.

Microorganisms need oxygen. Turn or aerate the compost tocirculate oxygen throughout the mix. Also, don't squash the compostdown. Without sufficient air, compost will turn into slime.

Likewise, compost critters like their environment to be moistbut not wet. (Think of a damp sponge.) Too much water will drownthem (and your compost will smell like a swamp). Too little andthey die before their work is done.

To maintain moisture, add grass clippings or other green waste.If adding dry material (straw, autumn leaves, shredded newspaper),sprinkle these ingredients with water before adding. If the compostlooks dry, spray it.

As the organisms eat, they generate heat, which speeds up decay.Ideally, the compost reaches 140 to 160 degrees, hot enough to killweed seeds and some plant diseases. Too much heat can be dangerous;unattended compost piles can spontaneously catch fire.

After 24 hours, the compost should feel warm to the touch. Ifnot, add more green (high-nitrogen) material. If it smells likeammonia, add more brown (high-carbon) material.

Bin vs. pile: A bin gives structure to the process and helpsspeed it along. Yard waste composted in a pile or heap will breakdown, too, but takes a lot longer (up to a year) and doesn't get ashot, allowing weed seeds to sprout. Also, a bin easily can becovered to keep out rodents and other pests. Make sure the bin hasgood drainage to eliminate excess moisture.

Size: Ideally, bins should be about 3 feet wide by 3 feet deepby 3 feet tall. In a smaller bin, the compost won't generate enoughheat to break down quickly. Larger, the compost becomes difficultto turn.

Time: Composting needs at least 30 days. The compost is readywhen its ingredients are thoroughly broken down and unrecognizable.It looks and feels like dark, rich soil.

Ingredients: Feed your compost critters a "balanced diet," halfgreen (fresh ingredients, rich in nitrogen) and half brown (driedmaterial as a source of carbon). For example, if you use all grassclippings, they'll clump together and not break down. Instead, mixthe grass clippings with an equal amount of shredded newspaper(it's a wood product and composts well). Cut material into smallerpieces; it breaks down faster.

Most fruit and vegetable kitchen waste can be composted. So cancoffee grounds (including the paper filter), tea bags and crushedeggshells. Cut citrus into pieces and cover with at least 6 inchesof dried material. Avoid banana peels (too slow to degrade) andlimes (too acidic).

Manure (horse, cow, sheep, rabbit or poultry) is very high innitrogen and stimulates compost activity. Use some manure to starta new batch.

Other compostable material: Dried leaves, landscape trimmings(preferably cut into 2-inch pieces), wood chips, sawdust, shreddedwhite paper, shredded paperboard (such as cereal boxes) or paperplates, paper napkins, brown paper bags (torn into pieces), straw,seaweed and pine needles. Avoid palm fronds -- they're tootough.

Don't compost fats or oils (including salad dressing, peanutbutter, etc.), pet droppings or animal products such as milk,cheese or bones. They attract pests to the pile and can spreaddisease.

Helpful links:

-- Composting101.com

-- Howtocompost.org

-- Organicgardening.com

-- CompostInstructions.com

(Distributed by Scripps Howard News Service,www.scrippsnews.com.)