Compost can be made by a cold process or a heated process. All plant and animal material will decay in time. A pile of this material left on its own will also compost in time. The advantages of this cold process of composting is that it takes less of your time and labor. The disadvantages are that it takes the pile longer to become compost and it may contain seeds and plant pathogens. The heated pile is built and maintained in a way that allows the pile to speed decomposition and produce enough heat to kill seeds and pathogens. The photos illustrate building a heated compost pile.
Building a compost pile requires four basic ingredients - nitrogen, carbon, water and oxygen. The addition of a small amount of good organic soil, quality compost or compost inoculant will add microorganisms that may speed the decomposition of the pile.
Nitrogen: Lawn clippings, green plants and green plant cuttings, fruit and vegetable peels, apples cores, blood meal, coffee grounds and manure are all good sources of nitrogen. Do Not use dog, cat or human manure.
Carbon: Carbon containing materials are usually brown such as leaves, hay and straw. Wood ashes can be used sparingly. Because they are very alkaline the high pH levels can limit microbial activity. They are a good source of calcium and potassium.
Water: You should keep your compost moist. The microbes need water, however, too much water will force the air out of the pile making conditions right for undesirable microbes and unpleasant odors. If the pile becomes too dry you can spray it with water as you turn it. Properly made compost will have a pleasant earthy smell.
Oxygen: As the microbes work in the pile they will deplete the oxygen supply. For this reason you should turn the pile periodically to incorporate more air. A well made pile will heat to 130 or more degrees. A compost pile containing manure should heat to between 131 degrees and 170 degrees. When the temperature reaches its peak and begins to decline you should turn the pile. It should be turned about five times before completion and maintain a temperature above 131 degrees for a total of 15 days.
You can see in the photos that we used pallets to create a composting area. Between the pallet boards we stuffed hay to control air movement. The hay allows some air to enter but not enough to dry the material. Notice in the photos a pile of green plant material, a pile of hay (this is bedding from our guinea cage that contains their manure) and a black garbage bag containing leaves on the ground near the compost bin. As we build a pile, first we apply a layer of hay and leaves, next a layer of green material and finally a thin layer of ready made compost to add microorganisms to the pile and sprinkle each layer with water. We repeat this layering until we have about four cubic feet of material in the pile. You need this amount of mass to produce the appropriate heat in the pile. Several bins connected together allow us to turn a pile by simply forking it from one bin into the next bin. The top is covered with hay to keep it from drying out. Then I cover it with a compost cover to keep rain from the compost. A well made pile can be ready in about 6 weeks.
The Rodale Book of Composting provides additional easy to follow instructions for making and using compost plus helpful tips for apartment dwellers,suburbanites, farmers and community leaders. Also included are ecologically sound solutions to growing waste disposal problems. Learn to recycle household and yard wastes in soil-enriching compost. Use the link below to read more.