VERMICOMPOSTING: TRANSFORMING GARBAGE INTO GOLD
Sustainable agriculture production systems are expected to provide quality food while meeting the various socio-economic and environment requirements of society.
Continuous use of chemical fertilizers over the years without caring for maintaining the soil balance has become counterproductive. Scientists are getting concerned about the situation and suggesting to use bio-fertilizers and other organic manures in adequate quantities in order to maintain the soil balance. Farmers are now convinced about the important of organic manures but availability of the good quality organic manures is the problem. The vermi-compost production would be a viable option to produce the good quality compost in short time. A growing number of individuals and institutions are taking interest in the production of compost utilizing earthworm activity. Krishi Vigyan Kendra-Jammu is giving free training for this technology to the farmers and field functionaries of the line departments.
Vermi-compost is produced as the vermi-cast by earth worms feeding on biological waste material and plant residues. This compost is an odorless, clean organic material containing adequate quantities of N, P, K and several micronutrients essential for plant growth. About 25-50 per cent of nitrogen can be reduced by adding 10 tones vermi-compost per hectare. It not only saves the cost of fertilizers but also increases the yield by 5-10 per cent. Besides higher concentration of available nutrients than the ordinary FYM, it has also been reported to enhance plants ability to fight against insect pests and diseases. It also improves soil structure due to presence of soil binding chemicals and improves physical properties of the soil like soil air, soil temperature, soil-water retention and soil mechanical impedance. There is a growing realization that vermi-composting provides the nutrients and growth enhancing hormones necessary for plant growth. The fruits, flowers, vegetables and other plant products grown using vermi-compost are reported to have better keeping quality.
Dr. Sanjay Swami
Diversity of earthworm species varies with different types of soils and hence choosing a local or native species of earthworm for the local soil and for vermi-composting is an important step. For Jammu region, the earth worm spp. Esenia foetida is best suited for vermi-compost production. The earthworms can be cultured or used in composting applying simple procedures either in pits, crates, tanks, concrete rings or any containers. Organic material to be used is recommended only after pre-processing or pre-digestion of respective material through partial anaerobic phase done under black polythene cover or with a clay seal layer. The bio-dung composting technology is highly recommended as a pre-digestion mechanism.
Compost pit of any convenient dimension can be dug in the backyard or garden or in a field. The most convenient pit of easily manageable size is 2m x 1m x 0.75m. A tank may be constructed with brick and mortar with proper water outlets, or a plastic crate (600 mm x 300 mm x 300 mm) with holes drilled at the bottom or empty wooden crates (deal wood boxes/apple cases) or well rings made of cement or clay of 750 mm diameter and 300 to 450 mm height can also be used with slight modifications in the thickness of layers used. Vermi-bed is the actual layer of good moist loamy soil placed at the bottom, about 150 to 200 mm thick above a thin layer (50 mm) of broken bricks and coarse sand. Earthworms are introduced into the loamy soil, which the worms will inhabit as their home. About 100 earthworms may be introduced into a compost pit of about 2m x 1m x 0.75m, with a vermi-bed of about 15 to 20 cm thick. The vermi-bed should always be kept moist, but should never be flooded.
Handful lumps of fresh cattle dung are then placed at random over the vermi-bed. The compost pit is then layered to about 50 mm with dry leaves or preferably chopped hay/straw. For the next 30 days the pit is kept moist by watering it, whenever necessary. The bed should neither be dry nor soggy. The pit may then be covered with leaves or an old jute (gunny) bag to discourage birds. Plastic sheets on the bed are to be avoided as they trap heat. After the first 30 days, as above, wet organic waste of animal and/or plant origin from the farm or kitchen that has been pre-digested is spread over it to a thickness of about 50 mm. This can be repeated twice a week. All these organic wastes can be turned over or mixed periodically with a spade. Care should be taken not to disturb the vermi-bed in which the worms live. Keep adding garbage till the compost pit is nearly full. Continue to keep the pit moist for another 30 to 45 days, turning over the material in the pit with care avoiding injury to the worms. Turning over can be done on every fifth or seventh day with the help of a forked spade. Regular watering should be done to keep the right amount of moisture in the pits. In 60 to 90 days the compost should be ready as indicated by the presence of earthworm castings (vermi-compost) on the top of the bed. Vermi-compost can now be harvested from the bin/pit. The material should be placed in a heap in the sun so that most of the worms move down to the cool base of the heap. The compost is then sieved before being packed. The earthworms and the thicker material, which remains on top of the sieve, go back in the bin and the process starts again. Compost works best with a mixture of coarse and fine materials, layered together. Vermi-compost is eco-friendly, non-toxic, consumes low energy input for composting and is a recycled biological product. In short, earthworms, through a type of biological alchemy, are capable of transforming garbage into “gold”.