What is Compost?
There is some confusion as to what compost actually is, and what it does. Compost is the result of plant or animal-based matter decomposing in a controlled manner. The end result is a substance which is rich in nutrients and can be used as a soil conditioner to help plants grow. Compost is the product of the act of composting.
What compost is not
Strictly speaking, compost is not the same as humus or humic matter. Compost contains humus but where humus takes centuries to break down, compost changes relatively quickly. When it is added to the soil, it breaks down further and is incorporated into the soil as it is used by microbes, insects, plants and other soil-residents. This is a practical difference: it explains why compost should be added annually or at least more than once to soil.
Also, strictly speaking, compost is not a fertiliser, even though it is often described as such (including by us). A fertiliser adds nutrients to the soil. It does not directly change the soil (although modern science confirms that its usage can degrade soil quality over time).
What compost is: an amendment
Compost is actually a soil amendment. An amendment, as its name suggests, changes the soil, generally in a positive manner. The soil improvement resulting from the addition of compost ensures that plants can make use of available nutrients. This is true whether they are found naturally in the soil or they result from fertilisation. There are many other amendments. The most common of these are lime, to raise the pH of alkaline soils, and sulphur, to lower the pH of acidic soils.
Compost does contain low levels of plant nutrients.However, its primary role is not to feed plants but to improve the soil so that plants can feed themselves.
What is compost for?
So, you know the strict definition, but what does compost actually do?
Compost is food for the soil, which in turn helps plants and food to grow. Composting food is also good for the environment as it gives back to the carbon cycle. So, compost is an extremely positive material. Anyone can make compost at home using food and garden waste. The best way to make good compost at home is our CarbonCycle Composter,
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