Method of composting

A. Pit method

It is the simplest method of compost making.

1. Dig a pit 2m long, 2m wide and 1m deep. However, the length and width of the pit may change according to the amount of compost to be made.
2. Fill the pit about 30cm deep with plant materials. The plant materials, if dry, wet them so that it contains about 50-70% moisture.
3. Components such as animal manure, bedding and urine (or 1 part livestock manure to 10 part water) along with a few handful of lime and some surface soil or previously prepared compost should be applied in thin layers every 30 cm.
4. Repeat the steps 2 and 3 until the pit is filled 50cm or more above the surface of the soil.
5. Plaster the rounded heap with cow-dung mud slurry.
6. After 3 months remove the materials from the pit and place it in a heap and replaster as above.

After another month or two the compost will be ready for use in the fields. In principle, the more a farmer turns his compost from the pit, the sooner he get6s compost for use in the field. The one-month turning method described in the preparation of improved FYM in the preceding section can be used to prepare compost involving turnings. Filling the pits should be followed as above and turning of materials are done every month as in case of one month turning method of FYM preparation.

B. Heap method

During monsoon a heap method of composting is preferred because the pits are easily water logged.

Composting is done by pilling the materials above ground in a heap. The simplest form of heap is described below. The size of the heap should be determined by the amount of materials available for composting. In any case the amount should not be less than 1 m3 and the height of the heap should not exceed 2m.

1. Pile the compost materials on the top of wood, old branches or rocks to ensure good aeration up to a height of about 30 cm.
2. Apply a thin layer (about 5cm thick) of starter materials consisting of cow-dung and urine water slurry, some superphosphate, or lime, some surface soil or plant ash, etc.
3. Repeat steps 1 and 2 until the height of the heap is about 2m. insert bamboo poles along the heap to serve as air vents and then enclose the heap with a thin cow-dung mud plaster. Remove poles after 1 to 2 days when the temperature in the heap is risen. (60-700 C).
4. After about two weeks open the heap, turn and reseal. Add water, if required at this point. the compost is ready for use after 3 months.

If sufficient amounts of compost is available 10-30 tons/ha can be applied per year with beneficial effects on soil properties and crop yields.