Vermicomposting

Vermicomposting is the process by which worms are used to convert organic materials (usually wastes) into a humus-like material known as vermin-compost. The goal is to process the material as quickly and efficiently as possible.

Vermicompost appears to be generally superior to conventionally produced compost in a number of important ways:

• Vermicompost is superior to most composts as an inoculant in the production of compost.
• Worms have a number of other possible uses on farms, including value as a high-quality animal feed.
• Vermicomposting and vermiculture offer the potential to organic farmers as sources of supplemental income.

Vermicompost has the following advantages over chemical fertilizers:

• It restores the microbial population, which includes nitrogen fixers, phosphate solubilizers, etc.,
• Provides major and micro-nutrients to the plants,
• Improves soil texture and water holding capacity of the soil,
• Provides good aeration to the soil, thereby improving root growth and proliferation of beneficial soil microorganisms,
• Decreases the use of pesticides for controlling plant pathogens,
• Improves the structural stability of the soil, thereby preventing soil erosion,
• Enhances the quality of grains/fruits due to increased sugar content.

At the same time, the beginning of the vermicomposting process is a more complicated process than traditional composting:

• It can be quicker, but to make it so generally requires more labour.
• It requires more space because worms are surface feeders and will not operate in material more than a meter in depth.
• It is more vulnerable to environmental pressures, such as temperature, freezing conditions, and drought.
• Perhaps most importantly, it requires more start-up resources, either in cash (to buy the worms) or in time and labour (to grow them).

Process of Vermicompost

In this process, the organic solid waste is converted through earthworm consumption into worm castings. Decomposition of organic matter in the earthworm occurs in the alimentary tract by micro-organisms inhabiting the gut.

Microbes such as fungi, actinomycetes, protozoa etc are known to inhibit the gut of earthworms. The ingested organic waste is first subjected to size reduction in the anterior part of the worms gut followed by its decomposition.

The worms species that are commonly active in this process are Pheretima sp. , Eisenia sp. And Perionyx sp.

These species survive in the temperature range of 20-40 degree Celsius and moisture range of 20-80%. They do not survive in pure organic substrate containing more than 40% fermentable organic substance

Hence fresh water is commonly mixed with partially or fully stabilized waste before it can be vermicomposted. The worms are known to be adversely affected by high concentration of heavy metals such as Cd, Cr, Pb & Zn.

Vermicomposting of wastes in field pits

• It is preferable to go for optimum-sized ground pits of 20 ft length, 3 ft width, and 2 ft deep for effective vermin-composting beds.
• A series of such beds is to be prepared at one place.

Vermicomposting of wastes on ground heaps

• Instead of open pits, vermicomposting can be taken up in ground heaps.
• Dome-shaped beds (with organic wastes) are prepared, and vermicomposting is taken up.
• The optimum size of ground heaps maybe 10 ft length × 3 ft width × 2 ft high.

Materials required for vermicomposting

• farm wastes (straw from wheat, soybean, chickpea, mustard, etc.) were used for vermicomposting
• fresh dung
• wastes: dung ratio (1:1 on a dry weight basis)
• earthworm: 1000–1200 adult worms (about 1 kg per quintal of waste material)
• water: 3–5 L in every week per heap or pit