A study was conducted to find the impacts of fly ash (FA) on the growth of cucumber and radish seedlings and also its effects on eri silkworm growth. Fly ash at the concentration of 5% (dry weight basis) enhances the seed germination percentage (94.02%) and at the higher concentration of 10% fly ash increases the root-shoot ratio (87.66%), relative water content (95.5%) and vigour index (647.67) of cucumber. Similar response of increases in all these parameters was also observed in radish seedlings treated with fly ash. The physiochemical properties of FA amended soil (5%) showed that available phosphorous (42 kgha-1) and potassium level (306 kgha-1) was increased respectively to 9.52% and 53.92% while compared to its control treatment. Laboratory rearing of eri silkworm on a natural host is not time-consuming. To overcome these oblige, incorporation of fly ash in their natural diet was developed and they enhanced the growth and fecundity rate of eri silkworm. However, Energy dispersive analysis (EDAX) of castor leaves treated with FA at 10% concentration revealed that five major minerals were observed which includes Magnesium (7.02%), Silica (12.69%), Chlorine (9.27%), Potassium (16.39%) and Calcium (32.14%). Further, the FA(5%) incorporated castor leaf pointedly enhanced the pupation rate (91.35%), shell weight (0.57 mg), cocoon shell ratio (19.073%), fecundity (526.22 eggs/female) and egg hatchability (94.32%) of the silkworm. In contrast, pupal weight was increased at lower concentration of fly ash (1.25%)with a weight of 2.39 mg. A significant difference was observed in rearing performance of eri silkworm and they depend on the percentage of FA incorporated on castor leaf. Relative growth rate (RGR) of the eri silkworm was increased to 84%when larvae treated with FA at 5% concentration. The purpose of this paper is to explore the possibility of FA addition into soils for improving nutritional properties and also incorporate the same in sericulture industry.