by Donald Zouras
August 20, 2005
From the beginning of the project in 2004, we decided that we wanted to limit the amount of natural materials that leave Native Suburbia. One corner of our relatively small backyard is dedicated to composting. Some people think it looks ugly, but we feel that the benefits outweigh any negative aspects. Composting is a good way to recycle leaves and other yard or kitchen waste. Instead of paying to haul it away in a big gas burning truck, we are allowing nature to help with the disposal. Using compost improves soil structure, texture, and aeration and increases water-holding capacity. This improves soil fertility and stimulates healthy root development in plants. The organic matter provided in compost provides food for microorganisms, which keeps the soil in a healthy, balanced condition. Nitrogen, potassium, and phosphorus will be produced naturally by the feeding of microorganisms, so manufactured fertilizers will not need to be added.
Composting is the process where organic matter decays as a result of piling it up and allowing it to decay through the natural process of decomposition. Pile up any organic matter and it will decompose eventually.
The amount of effort required to compost is up to you. Passive composting involves the least amount of time and energy on your part. This is done by collecting organic materials in a freestanding pile. It might take a long time (a year or two), but eventually organic materials in any type of a pile will break down into finished compost. Managed composting involves active participation, ranging from turning the pile occasionally to a major commitment of time and energy. If you use all the techniques of managing the pile, you can get finished compost in 3-4 weeks. Choose the techniques that reflect how much you want to intervene in the decomposition process and that will be a function of how fast you want to produce compost. Since the initial goal of the Native Suburbia project was reduce the yard maintenance effort, we are taking the passive approach.
The composting process involves four main components: organic matter, moisture, oxygen, and "composting critters".
Organic matter includes plant materials and vegetarian animal manures. Organic materials used for compost should include a mixture of brown material (dead leaves, twigs, manure) and green material (lawn clippings, weeds, fruit and vegetable scraps). Brown materials supply carbon, while green materials supply nitrogen. The best ratio seems to be a matter of opinion. Achieving the best mix is more an art gained through experience than an exact science. We have decided to just use whatever we have available and not worry much about the ratio. Shredding, chopping or mowing your composting materials into smaller pieces will help speed the process by increasing the surface area. Carefully consider any decision to put animal remains or meat and fats from cooking in the pile. While they may be rich in nutrients, decomposition of these materials may also produce unpleasant odors and attract scavengers. Do not add pet shit to compost as this increases the possibility of disease transmission to humans.
Moisture is important to support the composting process. Compost should be comparable to the wetness of a wrung-out sponge. If the pile is too dry, materials will decompose very slowly. Add water during dry periods or when adding large amounts of brown organic material. If the pile is too wet, turn the pile and mix the materials. Another option is to add dry, brown organic materials. If you, like us, do not care how quickly decomposition occurs, you can just sit back and let nature take its course.
Oxygen is needed to support the breakdown of plant material by bacteria. To supply oxygen, you may turn the compost pile so that materials at the edges are brought to the center of the pile. Wait at least two weeks before turning the pile, to allow the center of the pile to "heat up" and decompose. Once the pile has cooled in the center, decomposition of the materials has taken place. Frequent turning will help speed the composting process. Instead of turning our pile, we have created air gaps by composting the thin twigs which fall from our river birch trees. This keeps the organic material in our yard as well as adding to the potential compost we will create. Of course the woodiness does result in slower decomposition, but we are following the passive methodology, so this is not a concern.
Compost is the end product of a complex feeding pattern involving hundreds of different organisms, including bacteria, fungi, worms, and insects. By supplying organic materials, water, and oxygen, the already present bacteria will break down the plant material into useful compost for the garden. As the bacteria decompose the materials, they release heat, which is concentrated in the center of the pile. You may also add layers of soil or finished compost to supply more bacteria and speed the composting process. In addition to bacteria, larger organisms including insects and earthworms are active composters. These organisms break down larger materials in the compost pile to be finished off by the microorganisms.
Now that you know how to compost, where will you locate your compost pile? Any pile of organic matter will eventually rot, but a well-chosen site can speed up the process. Look for a level, well-drained area. Build the pile over soil or lawn rather than concrete or asphalt, to take advantage of the earthworms, beneficial microbes, and other decomposers, which will migrate up and down as the seasons change. Uncovered soil also allows for drainage. If you plan to add kitchen scraps, keep it accessible to the back door. Don't put it so far away that you will not want to make the trip. We suggest keeping a covered container in the kitchen, which can be taken out every few days. In cooler latitudes, keep the pile in a sunny spot to trap solar heat. Look for some shelter to protect the pile from freezing cold winds which could slow down the decaying process. In warm, dry latitudes, shelter the pile in a shadier spot so it doesn't dry out too quickly. In the end it usually comes down to deciding where you have room. In a small suburban yard like ours, there was only one reasonable choice. We built a small wall out of spare landscaping blocks to separate our pile from the rest of the yard. We hope that when the plants get established, they will further screen it from view.
Once you get everything set up then sit back and wait for nature to work
some magic. Finished compost is dark and crumbly like healthy soil.
Small pieces of leaves or other ingredients may be visible, but it generally
does not resemble the original contents. Compost has an earthy smell.
If it smells like ammonia or "rotting", it should be processed
longer. Compost that has not thoroughly processed could be hot with high
ammonia content. This could burn plant roots or leaves. We do not
have much experience with this step because we have only been composting
in significant amounts for about 5 months. There is no sign of finished
compost yet, but we are willing to wait. If only we weren't so busy
looking at all the plants and animals, there would be more time for playing
in the pile of decaying plants.
Understanding how to make and use compost is in the public interest, as the problem of waste disposal climbs toward a crisis level. Landfills are brimming, and new sites are not likely to be easily found. For this reason there is an interest in conserving existing landfill space and in developing alternative methods of dealing with waste. Don't throw away materials when you can use them to improve your yard and garden. We hope that you will start composting instead.
In addition to our own experiences, we gratefully acknowledge that much of this information was obtained from the following web pages: