What can be composted? The short answer is, just about any material that was previously alive at some time, that you can gather from your homesite or import in from the community, is fair game for a well-maintained compost pile (in addition, you might add certain inorganic materials if your soil requires them, for the advance processing a compost pile can provide). The real substance of compost is the organic refuse that comes from your garden and kitchen. The greater the variety of plant debris that you can introduce ... the better your compost will be, because it will contain not only the major plant elements (N/P/K), but also a wide variety of important trace elements (far more trace elements than any chemical fertilizer you can buy).
Let the following long list be just a guide to encourage you to use your imagination to put a wide variety of materials into your compost pile:
Is there anything you should not add to the pile? In theory, if it will decompose, it can go in the pile ...however, in real life you have to draw the line somewhere. You should not put any meat, fat, or bones in the pile as they will produce odors that will draw flies, rats, and other vermin. Walnut and bamboo leaves contain substances that inhibit plant growth. Some say you should not use any diseased plants or plants infested with insects. A properly built and maintained compost pile will achieve high enough temperatures to kill plant pathogens and insects; and the heat and microbial action may eliminate the effects of walnut and bamboo leaves.
Beware of using grass clippings, or any other material that has been treated with any of the various 'cides; Pesti-, Fungi-, Insecti-, and Herba-. Composting may help to break these dangerous chemicals down, or at least buffer them; but it is safer not to introduce any of these chemicals to your compost. You will have to find your own way here, although if you keep any questionable material down to 25% of the pile, you will probably be safe.Water
Water is critical to the decay process. Sufficient moisture must be present for the microorganisms to flourish. On the other hand, too much moisture will cool the pile down; and can cause it to go anaerobic. The goal is to try to achieve about a 50% moisture content. If you have a large amount of wet kitchen wastes, you may need to balance that with a lot of dry material. If you have a lot of dry material, be sure to have a garden hose on hand in order to lightly wet the pile during construction. We will cover this more thoroughly in the sections on Making and Managing the compost pile.
For the best results, the pile should contain plenty of microorganisms (bacteria, molds, fungi, etc.) and a healthy number of larger organisms (mites, beetles, worms, and such). Research has shown that it is not necessary to use any commercial compost starters, as the spores of the decomposer microorganisms are everywhere; as soon as you provide the proper environment of organic matter (Carbon and Nitrogen), oxygen, and moisture, they will begin their work.
Manure is not necessary to make compost. Old-timers among us will claim that it is the basis of good compost. Manure is great stuff; it is a compost all by itself. If you can get some, by all means use it (now I'm talking about the real thing, not some ancient stuff in a plastic bag that has long since lost its bacterial life). The amount to use is the amount you can get. It is estimated that 1/3 of the mass of manure is bacterial life. However, manure is not necessary to supply nitrogen; in fact, if you use a high proportion of kitchen wastes in your compost, your problem may be one of supplying enough dry carbonaceous material.
Many an authority advises using soil in your compost. The reasoning is that using soil introduces soil bacteria and worms to the compost. But as we have seen, this is not really necessary nor desirable, as the decomposer organisms are everywhere; and if you supply plenty of organic matter ... just try keeping the worms away. Soil will make the composting materials heavier to turn. One other use of soil by some is to act as a deodorant covering for the top of the pile (but if you are going to turn the pile often, as I suggest you do, then the soil will be mixed in with the other materials soon anyway). If you do decide that you want to use soil in your compost, at least use fertile topsoil, and not some sterilized potting soil from a bag.Air
Good air circulation is the final basic requirement for a successful aerobic compost pile. The aerobic microorganisms that are decomposing the pile need oxygen to survive. When making the pile, include plenty of coarse materials and don't pack the pile. A well-built compost pile is constructed to allow plenty of air circulation. However, aerobic piles can have areas of anaerobic conditions; this is the case when the center of the pile has air excluded by using material that is too fine-particled, or becomes water- logged from rains. We'll cover this some more in the section on Managing the compost pile.Additives / Conditioners
The use of any supplemental ingredients largely depends on the specific condition of Your soil. The best way to determine the needs of your soil is to test it. There are several good, inexpensive testing kits on the market (which will not only let you determine the exact condition of your soil, but also explain how to custom-tailor your fertilizer for your specific needs). You can also have your soil tested by your local County Extension Agent, and often garden nurseries offer testing free, or for a slight fee.
A comprehensive discussion of fertilizers is beyond the scope of this composting manual; however, the basics as they apply to composting, and some suggestions, follow. By all means, if your testing determines that a fertilizer is needed; add it to the compost first. The fertilizer will aid the decomposition process, and the microbial action will convert the fertilizer to forms more readily used by the plants, and longer lasting in the soil. Commercial sources are available for all fertilizers, organic or chemical, but you should strive to find waste sources whenever possible to keep costs to a minimum.
© 1998-2016 Jim Fish Rancho Mondo Productions (ranchomondo.com) All rights reserved.