Daniel Gill, Merrill, Thomas A. | 11/23/2006 1:57:57 AM
By Dan Gill
LSU AgCenter Horticulturist
This time of the year deciduous trees drop tons of leaves. Most people rake them up, put them in bags and place the bags on the curb to be picked up with the trash. What a shame!
You can recycle these leaves back into the landscape through the process of composting. Returning this organic matter to the garden maintains natural biological cycles and is an ecologically sensible means of recycling organic waste.
The composted material – or "compost," as we call it – is used primarily in garden or landscape bed preparation to improve the soil. Partially composted material also can be used as mulch.
Better yet, since homemade compost is free, it helps reduce the cost of gardening. (Or it means there’s more money left over to buy plants.)
Compost piles should be located in a convenient, but out-of-the-way, location. A source of water nearby is helpful. Make the pile from about 3 feet wide by 3 feet deep by 3 feet high up to about 5 by 5 by 5 in size. Anything smaller will not decompose as well, and larger piles are more difficult to work.
You can compost just by stacking organic matter in a pile, but most gardeners prefer to enclose the pile in a bin. Although there are a number of commercial bins on the market, you can make your own very easily. A 15-foot-long piece of hardware cloth or fencing wire bent into a circle and fastened with a few pieces of wire is inexpensive, easy to build and works well.
Organic matter decomposes naturally on its own. You can create compost simply by piling up leaves and other organic matter and allowing natural decomposition to take place. This is sometimes called passive composting. There is nothing really complicated about it, although using this method requires patience, and you must keep the organic matter moist. Depending on circumstances, it may take six months to 12 months for the organic matter to fully compost.
Typically, composting uses various techniques to speed up the natural breakdown of yard waste. It’s important to remember that raw organic material is converted into compost by the action of fungi and bacteria. In active composting, things are done to make these organisms work faster and more efficiently.
These fungi and bacteria require adequate nitrogen, oxygen and moisture to decompose organic matter rapidly. The composting process attempts to provide these requirements, and the better job you do the faster the process will occur. Shredding or finely chopping materials also greatly speeds up the process.
This time of the year, brown materials, such as brown leaves, are most of what’s available, and they are relatively low in nitrogen. Adding a commercial fertilizer or an organic fertilizer (such as blood meal) that contains nitrogen will encourage rapid, thorough decomposition when these types of materials constitute the bulk of what is being composted. A light sprinkling is applied over each 8-inch to 12-inch layer of organic matter as the pile is built.
Besides fallen leaves, a variety of organic materials also can be used for composting. These include grass clippings, shredded hedge clippings, raw vegetable and fruit trimmings and coffee grounds from the kitchen, dead houseplants and old flower arrangements. Manures, such as cow, horse, rabbit or poultry waste, make excellent additions to the compost and are relatively rich in nitrogen.
On the other hand, never put cooked foods, grease, meat, seafood scraps, fat and dog or cat droppings in the pile. Although these materials will compost, you increase the possibility of odor problems and attracting unwanted animals. Dog and cat droppings also may carry disease. It is also best not to put diseased plants or weeds that have set seed into the compost.
Oxygen is provided by enclosing the pile in a bin that has sides with a lot of ventilation openings that allow air to move in and out. Turning the pile occasionally is labor intensive, but it ensures the pile is well aerated and speeds decomposition.
During dry weather, watering the pile may be necessary maintain adequate moisture levels. Dry organic matter will not decompose. The pile should stay moist but not constantly soggy. A pile that stays too wet does not contain enough oxygen and may produce sour odors. If this happens, turning the pile will correct the problem.
You can throw an occasional shovel full of soil into the pile as you build it to supply the microorganisms that help start the decomposition process. The use of special compost starter or compost maker products is not really necessary.
As materials compost they lose more than half of their volume. When compost is ready for use, it should be dark brown and crumbly with much or all of the identity of the original material lost.
The time it takes to finish composting varies depending on the materials used, how finely they were chopped and good maintenance of moisture and oxygen. Two to six months is the typical cycle, but the process can occur much faster.
Get It Growing is a weekly feature on home lawn and garden topics prepared by experts in the LSU AgCenter. For more information on such topics, contact your parish LSU AgCenter Extension office or visit our Web site at www.lsuagcenter.com. A wide range of publications and a variety of other resources are available.