Composting converts plant material such as grass clippings and leaves into an organic soil amendment or mulch. It will be successful only if the following criteria are met: (1) Oxygen is required for efficient and non-smelly decomposition. Mixing the pile at least twice a month will provide oxygen and speed up the process. (2) Water so the pile is completely damp, but not soggy. Excess water limits oxygen, so do not overwater. (3) The smaller the material, the faster it will decompose. Shred leaves (easily done with a mower). Don’t use sticks over 1/4” in diameter without first chipping them. (4) The microbes “eating” the plant material require nitrogen for their own metabolism. One of the compost layers consists of a nitrogen source to supply this need.
What should you add to your compost pile? Leaves and plant trimmings can be added but are best just left on the lawn. If clippings are used, mix well with other waste, as they tend to mat down. Sawdust can be used in moderate amounts if additional nitrogen is applied (1 lb. for 100 lbs. of sawdust). Wood ash may be used at the rate of 1 cup per bushel (too much lowers nitrogen content excessively). Most disease organisms and weed seeds are destroyed if the pile reaches 160 degrees. If this temperature can’t be maintained, large amounts of weedy or diseased plants should be avoided. Small quantities of herbicide-treated plants (i.e. grass clippings treated with Weed-B-Gon) may be added if the compost is thoroughly decomposed before using.
Homemade compost structures are easily made. Two examples are diagrammed. The first is made of small-spaced wire fencing held together with chain snaps. The material is easily turned by moving the structure and turning the compost back into it. The second diagram shows a large compost bin that works like an assembly line. Start in one bin and turn into neighboring bins as the compost progresses. This structure is made out of wire and rot-resistant wood. The pile should be located away from drying winds and in partial sunlight. More wind and sun will require more watering.
Ideally, the composted pile should be about 5’ high. Start with any small twigs or other coarse material. Next add leaves, grass, and plant trimmings to a depth of 8”-10”. Water until moist but not soggy. Now add either 2” of manure or a commercial 10-10-10 fertilizer (one cup per 25 sq. ft. of surface area). Do not use fertilizer that has herbicide in it. Next add 1” of soil or completely decomposed compost. This adds microbes to decompose the waste. Repeat the layers in order, remembering to water after each leaf/grass/trimmings layer.
The pile should be turned occasionally. This helps prevent odors, hastens the process, and exposes weed seeds, insect larvae, and disease organisms to deadly temperatures (150-160 degrees). If these temperatures are not being achieved, the pile may not have enough oxygen or nitrogen, or may be too small, too dry, or too wet. Don’t turn the pile in the fall after the air temperatures cool. Adding small amounts of new material to a partially decomposed pile is okay if the pile is turned. If a large amount of new material is available, start a different pile. Compost is ready for use somewhere between 2-12 months, depending on how well the pile was maintained and what materials were used. When compost is finished, the pile will be about half its original size and the material will have an earthy smell and feel to it.
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