Sunday, July 6, 2008


Composting is like cooking. There is the simple recipe that has several variations.

"A good beginners guide is to use roughly half brown and half green materials when building your pile."

There are three types of composting
  • Hot Composting
  • Slow Composting
  • Closed Air Composting
(The information below was taken from

Hot Composting

The hot compost method depends on heat-loving and heat-generating bacteria. In order for these bacteria to thrive, the pile should be of correct size, have the proper temperature, and have the proper balance of food, water and air. The compost pile is really a teeming microbial farm. Microorganisms, such as bacteria and fungi, are naturally present on food and yard trimmings added to the pile. These organisms decompose organic material into rich, earthy-smelling organic material. The hot compost method depends on heat-loving and heat-generating bacteria. In order for these bacteria to thrive, the pile should be of correct size, have the proper temperature, and have the proper balance of food, water and air. If these conditions are met, the microorganisms will raise the temperature of the pile to 140 degrees or more; hot enough to burn your hand! The heat from this rapid decomposition is enough to kill most weeds and disease-causing organisms.

Proper Balance of Food
Just about anything that was once alive can be composted. Carbon and nitrogen from the cells of dead plants and microorganisms fuel the activity of the decomposing organisms. The ratio of carbon to nitrogen (C:N) is important to a hot compost pile. It helps to think of materials high in nitrogen as "greens," and carbon-rich materials as "browns." A good guide to get the right balance of greens to browns is to use roughly half browns and half greens when building your pile. A pile that is too high in browns will stay cool and sit a long time without breaking down. A pile too high in greens can get slimy and have a foul odor. Other household organic materials such as wool, cotton, dust, hair clippings, and pet fur can also be composted.

Materials Not To Use...

  • Food scraps of any kind
  • Large branches or logs (unless shredded)
  • Plastic or synthetic fibers
  • Manure from carnivorous (meat eating) animals
  • Diseased plants or plants suffering from severe insect attack
  • Weeds with seeds
  • Invasive plants and weeds (ivy, succulents, Bermuda grass, morning glory)
  • Plants that have been treated with herbicidesCharcoal ashes
Building The Compost Pile
  • Locate the compost pile in a shady location out of the wind to decrease water loss through evaporation. Multiple piles are recommended for different stages of composting.
  • Stockpile enough green and brown materials to make a pile that is at least one cubic yard in size. Piles smaller than 3 cubed feet will have trouble holding heat, while piles larger than 5 cubed feet will not allow enough air to reach microorganisms at the center.
  • The more surface area the microorganisms have to work on, the faster the materials will decompose. Cut or bruise yard trimmings with a shovel or machete, or put them through a chipper or shredder. Some materials may be run over with a rotary lawn mower. The harder or more woody the tissues, the smaller they need to be chopped.
    Alternate layers of green and brown materials. Begin with a thick layer of coarse, bulky material, such as sunflower stalks or flowers, to allow air to circulate in the pile. Next, layer greens and browns in the mix together. It is best to keep the layers thin. Continue mixing greens and browns until the pile reaches 3-4 feet high. Once the pile starts to "cook," do not add more materials.
Keep the pile moist
The compost material should be moist to the touch, but only yield a drop or two of liquid when squeezed. Moisten dry materials when adding them to the pile. A layer of straw, plastic or carpet scraps on top of the pile helps keep its outer edges moist.

Turn the pile
Ideally, the compost should cook along at 140 degrees of higher for at least three days. (Long thermometers are available to keep track of compost temperature.) When the pile cools, turn it. If a movable compost bin is being used, remove it from the pile, place it nearby, and move the compost into it with a shovel or pitchfork. If a multiple bin unit is being used, move the compost into the next bin. In several days, the pile will heat up a second time, though probably not as high the initial temperature build-up. After the pile has cooled again, it should be turned a third time. As you turn it, move any un-composted materials to the active center of the pile. Continue this process until the compost no longer heats up significantly. When most of the bulky material has decomposed, the compost is ready. Sift large chunks out of the finished compost for further composting.

Slow Composting

In the slow composting method, yard trimmings are composted in simple holding units or compost heaps. Bacteria and fungi that function at mild temperatures are the actors here. Earthworms, centipedes, beetles, millipedes and other organisms are also involved in the breakdown process.

Materials to Use
Use the same ingredients as the hot compost pile. Be sure to keep the kitchen scraps out as compost heaps can attract rodents.

Building the Compost Heap
Position the compost heap in a convenient spot out of the wind and direct sunlight. It is helpful to have two heaps; one to use for fresh materials while the other is maturing. Composting piles should be located directly on the soil.Add yard trimmings as they are collected. By mixing the green and brown materials, and keeping the heap damp (but not soggy), it will help keep the composting process going. Since materials are continually added to the heap, the more finished compost will be located at the bottom. To harvest the ready compost, remove the holding unit from the compost heap, and place it next to the heap. Next, shovel materials from the top of the old heap into the bottom of the empty holding unit until rich compost is found.

Closed Air Composting

Closed air (anaerobic) composting is done in a closed bin. Anaerobic microorganisms, which produce end products that can smell like rotting eggs, also become involved in the decomposition process. In closed air bins, water is continuously recycled as condensation, which drops back to the mass from the interior of the lid. This process helps the contents of the bin stay damp, a good feature given the Coachella Valley's dry climate. Materials to use is the same ingredients as the hot compost pile; with closed-air composting. However, kitchen scraps can be added. Do not add meat, bones, oils, fatty foods or dairy products.

The Closed-Air Composting System
Position the compost bin in a sunny spot if possible, to utilize the "glass house effect," which in turn encourages the entry, but not the loss of heat. It is best to have two composting bins; while the first is maturing, the second can be filled.Bins should be placed on soil that will allow drainage and the entry of earthworms and other beneficial organisms. Some closed-air systems require the bin to be placed over a hole 6-12 inches deep. Chop or grind large kitchen scraps and yard trimmings into smaller pieces, to hasten the composting process.Add materials to the compost bin once or twice a week. Try to avoid more frequent opening of the bin, and keep the lid tightly secured. Vary the layers of material, or mix them together when adding to the bin.It is very important that the compost material does not dry out. Add water, if necessary, to keep the compost moist. If the compost becomes sloppy, add dry ingredients to the mixture. You do not need to turn or aerate the contents of the bin.οΎ  Continue adding materials to the bin until it is full. The materials will reduce significantly in volume as the composting process takes place. When the bin is completely full, cover the compost with a thin layer of soil and allow it to sit for 12-16 weeks. The compost on the bottom of the pile will mature first. Some bins have a bottom opening to harvest this finished compost, while others require the bin to be pulled up over the mature compost.

If you are not into any of these methods of composting than check out Naturemill which is a company that makes a composting machine. It's safe, easy and good for those that have little to no hard space.

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