Earthworms are valued by farmers because, in addition to aerating the soil, they digest organic matter and produce castings that are a valuable source of humus. Vermicomposting, or worm composting is a simple technology that takes advantage of this to convert biodegradable waste into organic manure with the help of earthworms (the red worm Eisenia foetida) with no pile turning, no smell, and fast production of compost. The earthworms are bred in a mix of cow dung, soil, and agricultural residues or predecomposed leaf-litter. The whole mass is converted into casts or vermicompost, which can be used as a fertilizer on all types of plants in vegetable beds, landscaping areas, or lawns.
Worms are so effective at processing organic waste that they can digest almost half their own weight in debris every day. Vermicomposting is a simple composting process that takes advantage of what earthworms do naturally, but confines the worms to bins making it easier for farmers to feed them and to harvest their nutrient-rich compost. Since all worms digest organic matter, in principle, any type of worm can be used; however, not all are equally well adapted to living in bins since some worms prefer to live deep in the soil while others are better adapted to living closer to the surface. The red worm (Eisenia foetida) is ideal for vermicomposting because its natural habitat is close to the surface and it is accustomed to a diet rich in organic matter, this makes it ideally suited to digesting kitchen scraps and to living in bins.
WOCAT database reference: QT NEP 36
Location: ICIMOD Knowledge Park at Godavari, Lalitpur District, Nepal
Technology area: Demonstration plot
Conservation measure(s): Agronomic and management
Land Use: Annual/perennial cropping on rainfed agricultural land
Stage of intervention: Prevention of land degradation
Origin: Innovation through experiment and research
Other related technology: Improved compost preparation (QT NEP 7), Better quality farmyard manure through improved decomposition(QT NEP 8), Improved farmyard manure through sunlight, rain and runoff protection (QT NEP 9), Black plastic covered farmyard manure (QT NEP 16)
Compiled by: Samden Lama Sherpa, ICIMOD
Date: June 2011, updated March 2013