A plant or algae control composition is disclosed. The composition contains a herbicide and/or algaecide adsorbed onto a solid carrier. The composition may comprise a free-flowing granular product. The solid carrier contains a mixture of different clay materials. Two different clay materials are combined that synergistically mix together to allow for greater amounts of the herbicide or algaecide to be adsorbed onto the particles. The composition is particularly well suited for treating aquatic environments.
