By Trisha Gedon
STILLWATER, Okla. – One of the foundations of success when it comes to gardening is good soil. For those who don’t have naturally nutrient-rich soil already, composting may be an answer that also reduces the amount of waste going to local landfills.
Compost is a natural, dark brown, humus-rich material formed from the decomposition or breakdown of organic material such as leaves, grass clippings, vegetable food scraps and twigs, said David Hillock, Oklahoma State University Extension consumer horticulturist.
“Not only is it a great addition to your garden beds or pots, but also saves community waste-management resources because these things are now being composted instead of hauled to the landfill,” he said. “Compost can be used to improve soil structure, increase water-holding capacity of sandy soil, loosen clay soil and improve drainage, help with erosion control, mulch around landscape plants to retain moisture and more.”
Yard waste, especially grass clippings, typically are high in nutrient content. When composted, bacteria use air and water to break down plant materials into compost, which is great when applied as a mulch or used as a soil amendment.
Although commercial composting bins can be purchased, gardeners can make their own instead. The easiest method is to make a pile of compost material in an out-of-the-way space in the landscape – the far corner of a yard, for example. Another option is to build a confining structure about 3 to 5 feet in diameter and 4 feet tall. Hillock suggested using materials on hand such as concrete blocks, wire mesh, boards, old pallets or even old garbage cans with ventilation holes.
“Once the structure is put together, begin layering your green and brown materials. With spring in full swing, many people are in the process of cleaning up their yards and flower beds, so composting material should be plentiful,” he said.
Food scraps such as vegetable peels, eggshells, coffee grounds and tea leaves also can be used. Don’t use materials such as large branches, diseased plants, weeds that produce abundant seeds, pet or human waste, fatty foods and grease, meat, dairy products, bones or fish.
Hillock said alternating layers of materials helps ensure the correct carbon and nitrogen amounts required for decomposition. With water and air, bacteria and insects use the compost as a source of food and energy. The process generates heat ranging from 140 to160 degrees. Aeration is done by turning the pile on a weekly basis. Be sure to wet the material thoroughly to begin, then sprinkle with water periodically.
The more turning, the more air the bacteria have available, making the composting process move more quickly. When the temperature of the pile stays at ambient levels, even after turning, and the material is dark and crumbles easily, the process is done.
“Typically, it takes about four to six months to complete the process. If the compost pile is started now, you’ll have a great soil amendment ready when planting your fall garden,” he said.
More composting information is available in OSU Extension’s Backyard Composting in Oklahoma fact sheet. General gardening information also is available online at OSU Extension.