Organic Manures Cum Composting

Compost walls under consruction

Organic manures are plants and animal residues added to the soil by the farmer to maintain soil fertility. In our locality we make three types of these. They are Compost, Farmyard or Animal and Green manures.
I got the students involved in making the compost manure. We need refuse, vegetable materials, animal manure, wood ash and top soil as compost materials. These are kept in layers in 4 compost stacks. The first layer is refuse or old compost, followed by vegetable materials which the students provide. Third layer is animal manure (Goat and poultry droppings). Then wood ash, followed by top soil in that order. These processes are repeated until the required height of 1.2 metres is reached, except that the first layer made of refuse is only made once and for all. The finishing layer is made up of dry leaves.

Stack walls are necessary to keep the material intact. Water is also sprinkled to the compost. The materials are let to rot in stacks for 3 or 4 weeks, after which the first turning is done. The second turning takes place after another 3 or 4 weeks. If the compost is not used immediately, it is covered with polythene to protect it from sun and rain.

Pits and stacks are the 2 methods of composting. We prefer the stack method. The wood ash and animal waste added to the compost is referred to as starter because they accelerate decomposition of the compost by introducing bacteria and other organisms that help in the decay of the materials. In order to test decomposition, a stick described as tester is pushed into the centre of the stack. After a few days the stick is pulled out and the end buried in the compost felt. When it is hot, it shows bacterial activities, indicating that decomposition is going on. If the end of the tester is not hot, it means no decomposition and the compost is rebuilt.

Merits of compost include nutrient supply to the soil, improving soil structure and water holding capacity. Others are reduction of erosion and leaching, cheap, food provision to the soil and prevention of extreme of pH in the top soil. Its out standing disadvantage is that it is difficult to make for large scale farming. The relative end product of organic matter decomposition of the manure added to the soil is humus which provides a good porosity and water holding capacity of the soil. Loamy soil is the result of this and it is the best for production of most crops.

I asked the students to bring wood ash, animal waste and vegetable materials from home to make the compost. On the other hand, top soil is obtained from the compost site. We made the compost on the 3^rd December 2007 and it is due for first turning on the 31^st December 2007. The second turning comes up on the 29^th January 2008, on a 4-weekly basis. Since we shall not be using the compost immediately, it would be preserved for the appropriate time to use.

More in pictures ....

Students composting in groups