In recent years, edible mushroom cultivation in paddy straw has been practised in India. An attempt was made to utilize the water hyacinth, Eichhornia crassipes, as a substrate for oyster mushroom cultivation and a good yield was achieved. This was related to the ideal C/N ratio and low lignin content. This technology could be very cheap and it is also a method of helping to eradicate a troublesome aquatic weed.