Compost is a humusy soil amendment that is rich in organic matter, teeming with beneficial soil organisms and chock full of micronutrients that help plants grow. Composting happens when plant matter (and sometimes animal matter like manure, feathers, bone or blood meal) decompose. Decomposition is a natural process, and the ingredients of compost would have decomposed eventually whether they were composted or not.
Compost differs from the sort of decomposition you see in nature in that human intervention speeds up the process. For example, autumn leaves that fall in the forest may not fully decay for two years. But when composters blend shredded autumn leaves with nitrogenous “green” materials, water, and mix regularly, the leaves may decompose in a matter of weeks. By combining the right amounts of ingredients and using a compost bin or even just an open-air pile, composters are able to create blended compost that is great for the soil relatively quickly.
Although human intervention speeds up the process, the bacteria, fungi, nematodes, insects and earthworms that live in the compost bin are actually responsible for decomposing the ingredients. Bacteria and fungi use the nitrogen locked in green grass clippings, kitchen scraps and finished manure as fuel needed to digest the carbon in fall leaves, woodchips, straw and other “brown” materials. As these microscopic organisms feed on the contents of the bin, things begin to heat up – literally. The temperature of the compost pile rises and the speed of decomposition increases. As the contents of the compost bin begin to break down, earthworms and insects eat, digest, and mix the contents as well.
There are many different ways to compost at home. A wide variety of compost bins are available to purchase from local garden centers, box stores and online. There are even more designs available to build a system on your own. Probably the simplest (and definitely the least expensive) way to compost is to heap together ingredients in a simple pile somewhere in or near your garden. Regardless of how much time or money you’re able to invest in a home composting system, as long as you provide the decomposers in your bin with plenty of carbon, nitrogen, water and air, eventually compost will happen. All the ingredients to create fantastic compost can usually be found around your home landscape, and would otherwise be sent to a landfill as yard waste or kitchen garbage.
Finished compost does wonderful things when added to garden soil. Compost improves the texture of compacted clays, improves soil drainage yet increases water retention, spreads beneficial organisms and more. You can till compost into the soil, spread a layer on top of the soil, dig into the top inch of soil around trees or brew into compost tea to sprinkle around plants.