Composting Composting is the natural cycle of plants living, dying, and breaking down to pass their nutrients to other plants. Compost is a source of nutrients for plants. It helps to improve the texture and fertility of the soil. You learned about texture earlier in this case. Compost is made up of a lot of different things. Think of compost as the soil's diet. The diet should be balanced between materials that are strong in nitrogen and those strong in carbon, between wet and dry materials, and between acidic and basic materials. Microorganisms in the soil break down the organic matter to make compost. The basic compost pile is made up of layers of organic matter, sprinkled with a little soil and fertilizer, kept moist and turned to keep oxygen going through it. You can speed up the process by making the size of the organic matter smaller and by turning the pile frequently. There are four basic ingredients in a compost pile: Carbon (from organic matter like leaves) provides the food for microorganisms. Nitrogen (the fertilizer) comes from grass clippings and dead green plants and provides the energy microorganisms need to break down the carbon. Water and oxygen, which microorganisms need lots of to do their job.