Learn The Basics of Composting For Your Garden
How to get started adding nutrients to your soil.
By Cathy Babcock | Photography by Brian Goddard
Composting sounds like a science project—complicated and mysterious. While you do need to understand the basics, there is nothing secretive about the process. Scientifically speaking, composting is a degradation of organic wastes by microorganisms, such as bacteria and fungi, resulting in dark, crumbly, earthy-smelling, nutrient-rich material that can be used as an organic soil amendment.
Desert soil contains very little organic matter. Adding compost when gardening enriches all types of soils, opening up clay ones and aiding sandy soils in retaining moisture while simultaneously adding nutrients. Compost neutralizes the alkalinity of desert soils and reduces the need for chemical fertilizers.
So why consider composting? The obvious reason is that it reduces landfill waste. But composting is also a fun and inexpensive way to condition garden beds. Why spend money on bagged compost, the ingredients of which vary from brand to brand? You will receive genuine satisfaction from looking at your garden and knowing that the rich soil in which your plants are growing is a direct result of your efforts.
If you have a yard, you can create a compost pile. The first thing you need to do is find a location for it. Choose a place that is in the shade, out of the wind, easily accessible, sited directly on the soil for drainage and near a water source.
The area you choose should hold a pile that is about 1 cubic yard in size, or 3 feet long by 3 feet wide by 3 feet high. This will ensure that there is enough room for the materials to retain heat and moisture. Although the pile does not have to be contained, many gardeners find it easier to maintain if it is enclosed. For containment, any material can be used. Concrete blocks, wire mesh, plastic, untreated wooden pallets and recycled trash containers are common. Check with your city recycling department for free recycling containers.
There are two necessary types of materials used in composting: green and brown. Greens are wet, soft, green matter that is high in nitrogen. This includes vegetable scraps, fruit peelings, grass clippings, green leaves, coffee grounds and barnyard manure from chickens, horses, cows or goats. Browns are dry, harder materials that are high in carbon, including dried leaves, small woody prunings, shredded paper, sawdust, pine needles and straw. All materials should be shredded or chopped for faster decomposition.
Do not use meat, bones or dairy products, as they result in an unpleasant odor and can attract pests; grease or oils, which can inhibit air circulation and create a slimy feel; pet or human waste, which may contain harmful parasites; or grass and weeds with seed heads, runners or roots that might resprout.
Building a compost pile
Once you’ve chosen the spot for your compost pile, dig up about 2 inches of the soil and add a layer of small branches, which will facilitate air circulation from below. Starting with browns, layer and alternate with greens at a ratio of roughly three-quarters to two-thirds browns (carbon) to one-quarter to one-third greens (nitrogen) so there will be more carbon material than nitrogen material. Continue layering to a height of about 3 feet. Water lightly as you build to moisten everything, but don’t soak the pile. Using a pitchfork, turn weekly to keep it aerated.
Once established, new materials added can be mixed in rather than layered. Remember, turning the pile with a pitchfork is the key to aerating and speeding up the process. Keep the pile damp but not sopping wet. When adding green matter and kitchen scraps, bury them deep in the pile or add a shovelful of soil on top of them. Regularly sift and return larger, partially decomposed pieces to the pile for further breakdown.
After about three months, you should have rich mulch that is ready to use. The finished product will be crumbly and dark brown, and it should smell very earthy. Use your compost as a soil additive, not as a complete growing medium. Bury it in your garden beds and enjoy.