Water Lettuce Pistia stratiotes Water lettuce is a floating plant that grows in lakes, rivers and canals, and in warmer climates, occasionally forming large dense mats of bright green plants. Experts disagree as to whether water lettuce is a U.S. native plant or has been introduced, but if introduced, it was quite a while ago, the earliest reference in Florida was in 1765. varamey@nervm.nerdc.ufl.edu Copyright 1997 University of Florida How To Identify Water Lettuce Water lettuce is a free-floating plant. As its name implies, water lettuce resembles a floating open head of lettuce. Water lettuce has very thick leaves. The leaves are light dull green to blue-green, are hairy, and are ridged. There are no leaf stalks. Water lettuce roots are light-colored and feathery. Its flowers are inconspicuous. Water lettuce reproduces vegetatively by short runner stems (stolons) that radiate from the base of the plant to form daughter plants, and also reproduces by seed. How to grow Water Lettuce If given plenty of sun in a pool with fish to fertilize it, and a water temperature warmer than 70°F, water lettuce will grow up to 15 inches in diameter, and produce plenty of daughter plants.  With a start of three plants in the spring, they can produce enough plants to completely cover  a 10 foot by 12 foot area by mid summer. Back to Floating Plants Page