The organic wastes, like water hyacinth (WH), paddy straw (PS) and sawdust (SD) were collected from a local farm of Kharagpur, India. Before carrying out the experiment some common physico-chemical characteristics of organic wastes were analyzed (Table 1). Urine free cow dung, collected from a nearby dairy farm was used as the organic source to initiate as well as expedite the biological conversion process. Juvenile, non-clitellated specimens of epigeic earthworm E. foetida, weighing about 200–250 mg, were obtained from our experimental vermiculture unit and used for composting on organic mixed wastes. The experiment on biodegradable organic wastes was conducted in 2.0 l earthen pots with a small hole at the bottom. Three different biodegradable organic wastes, viz. Water hyacinth, paddy straw and sawdust with variable C/N ratios were used as food for E. foetida. Water hyacinth and paddy straw were chopped to reduce their size and volume by about 50–70%. Finely chopped substrates were dipped overnight in 0.1% formalin.