RICE HULLS or RICE HUSKS: are the hard protecting coverings of grains of rice. In addition to protecting rice during the growing season, rice hulls can be put to use after rice is harvested, the grains are dried and hulled before being polished, parboiled or "converted," or sold as brown rice. Rice hulls are thin, feather-light with the thin, pointed shape of rice grains. They can be used on their own, to lighten soil and improve both drainage and water retention. Or they can be added to potting mixes for seedlings and containers.