Farmers can use crop residues to make compost. Usually this is done by making heaps with alternating layers of organic waste, soil, chalk, fresh manure and green plant materials. A fermentation process will take place, which turns the material into a good organic fertilizer. There are many methods to make compost heaps or to compost the materials in a pit, but in all methods the presence of water and air is important.
In a good compost heap, the temperature will increase because of the composting process and can reach 55 to 60 °C. During this process, many seeds of weeds, pupae and larvae of insects and spores of diseases will be killed. Therefore, when pests or diseases are present in the field, making compost is better than just digging in plant residues.
Chemical fertilizers are often cheap and easy to use. But when only chemical fertilizers are used this will have a negative impact on soil structure and on the biological health of the soil. By regularly using a good organic fertilizer, the soil structure and health of the soil will improve.
Compost making has thus several advantages for the IPM farmer. It helps to improve the soil structure and fertility, which is needed to grow a healthy crop. Furthermore the composting process will remove a part of the diseases, pests and weeds, which could infest the crop in the following season.
Another way of composting is by using worms to decompose the plant materials. This is then called vermicompost.