Nature uses the process of decomposition to return nutrients to the soil for reuse. Composting harnesses the natural process, producing a product that you can add to your garden for soil improvement. You can compost a variety of organic material, including leaves, grass clippings, straw, fruit and vegetable scraps, and even manure.
Composting optimizes conditions for the growth of bacterial and fungal microbes—the organisms responsible for decomposition.
COMPOSTING REQUIRES OXYGEN
Turning your compost with a garden fork or by transferring it into another container helps with aeration. Although decomposition can occur without the presence of oxygen, aeration helps reduce odor and quicken the process. Aeration is especially important during the initial stage of decomposition. Remember to turn your compost pile daily.
KEEP COMPOST MOIST
Although some organic materials, such as fruit, already contain some water, it is important to maintain moisture. Rainwater and irrigation can both play a role in moisture management. Water enables higher levels of microbial activity. Take care, however, that your compost pile doesn’t remain too wet for too long. Too much water hinders aeration. Your compost pile should be located in a well-drained area.
During periods of excessive rain, consider using a temporary cover so that the compost is not over-saturated with water.
COMPOST PARTICLE SIZE
In “Home Composting: A Guide to Managing Yard Waste,” extension specialists affirm, “The smaller the particle size, the faster it will be turned into compost.” Microbes attack the outer layer of any given organic material. You can therefore speed up the process by shredding or breaking up organic materials before adding them to the compost pile.
FERTILIZING YOUR COMPOST
Microbes need carbon and nitrogen for energy and growth. Ideally, you want a mixture of high carbon and high nitrogen materials—thirty parts carbon source to one part nitrogen. Sawdust and straw are both high in carbon, but do note that they decompose very slowly and require additional nitrogen sources. Manure and blood meal are good sources of nitrogen, although you can use a commercial fertilizer in their stead.
Compost should maintain a temperature of 90 degrees or higher. The heat is produced by the bacteria breaking down the plant material. If your pile will not heat up, add more nitrogen.
Complete compost is often slightly alkaline in pH. Do not add lime to your compost pile as it will limit the availability of micronutrients such as iron, magnesium, and copper.
You can compost in piles, bins, or pits. Containing your compost within some form of structure generally hastens the process and helps with yard ascetics. Barrel and drum composters aid in turning your compost. Bin structures can handle larger amounts of compost. Three-chambered bins are common. If you use wood in constructing your compost bin, make sure to treat it so that it lasts longer than a year.
Compost structures also help maintain the moisture level throughout the compost pile.
When organic materials finish composting, they have about half of their original volume. Finished compost is dark brown or black in color, crumbly in texture, and earthy to smell. The pH will be between neutral and slightly alkaline. Composting takes time, often 90 to 120 days.
Finished compost itself is not a fertilizer, and you may need to add fertilizer after adding compost to your garden. The use of compost in heavy clay soil helps improve aeration, root penetration, and water infiltration. Compost is also good for mulching in landscapes or use as growing material indoors.
For more information on composting, visit University of Kentucky Extension Publications, or contact the Oldham County Extension office at 222-9453.
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