Use the Chemistry of Compost

• Plants need nitrogen, oxygen and other nutrients to grow. To get these nutrients, they produce chlorophyll, a chemical that helps process carbon dioxide and chemicals from the soil into carbohydrates that help them make plant tissue. When plants die or are mowed, pruned or pinched back, the carbohydrates, nutrients and carbon-based tissues that fill them break down--with the help of microbes, bacteria and insects--into the compounds that other plants can use to grow. When we remove dead plants or trimmings from the surface of our garden's soil, we must replace them--generally with fertilizers and synthetic soil amendments. Compost eliminates the need for these extra steps by using the compounds recovered from decomposition of the old plants to provide nutrients for the new ones. This happens with a little help from the compost keeper, who provides some "elbow grease" to speed up the process. The result is a home-brewed combination of recycled nutrients and new soil conditioners.
  
  

Committing to Compost

• The decision to begin composting in your garden requires some planning. The easiest bin is a wire or hardware cloth container that sits in the corner of the garden, collecting clippings, soil and dead plants for a few months to a year or two. A setup that produces a usable result more quickly, however, involves a set of boxes or large bins whose contents can be turned periodically. It often yields results after a few weeks. The "heap" (another name for a compost pile) should be located in a spot with good air circulation that is convenient to gardening chores. High-carbon waste like dead plants, sawdust and autumn leaves must be combined with high-nitrogen sources like grass clippings and green plants with a volume from 25 to 125 cubic feet. The heap must be kept continuously damp to start the process of decomposition. Once it begins, however, it will generate enough heat to kill most bad microbes and support the microbes that help complete the decomposition process.
  
  

Tending the Heap

• In addition to garden waste, paper, sawdust and vegetable kitchen waste (no meats and no oils) can be added to the heap. Once the process begins, the home compost practitioner will need to turn it frequently so that the materials process together. This may be accomplished by shoveling "green" compost to a second box as it ripens and into a third box to mature. Rotating containers means that some compost becomes ready as a new heap is started, making a continuous supply of well-rotted compost available. Compost can also be turned in one large box using shovels or special tools shaped like corkscrews. The heap must be kept spongy by adding water. It can overheat, even in winter. A finished heap cools down and contains worms, insects and a loose, rich soil-like material that can be used to fertilize and condition garden soil and other topsoil.