Study on phytoremedial capability of water hyacinth as a safe  organic manure source was done at the Regional Agricultural Research Station, Kumarakom during 2010-12. The heavy metals and other minerals in water hyacinth were Fe (33038 ppm), Al (13075 ppm), Ca (2234.80 ppm), Mn (1440.1 ppm), Mg (1608.3 ppm), Zn (77.08 ppm), Cu (49.80 ppm), Cr (23.37 ppm), As (5.276 ppm), Pb (0.531 ppm),  and Hg (0.151 ppm). The heavy metal contents in all the three forms of composts were almost  similar, except for Fe, Cr and Cd. The biomass yield of Amaranthus viridis in a pot culture study was higher in water hyacinth than  ordinary compost during the initial harvest, while yields for the final harvest and total yields were significantly higher for the farmyard waste compost. The heavy metals Pb, Hg and Cd content in Amaranthus remained unaltered by the organic sources, while As, Cr and Ni content were enhanced significantly by the water hyacinth treatments.