There are a number of reasons to have floating plants in a pond. The first, of course, is that when they are in their prime, they are among the more beautiful, and interesting, of all of the plants that are available to pond owners. From the tufty, multicolored mats of Azolla to the magnificent blossoms of Water Hyacinth, this is truly a varied group. Another reason is for algae control....

Free floating plants such as duck weed, water lettuce, and water hyacinth, though not necessary, add the finishing touch to a natural appearing water garden. These plants move with the breeze and produce an ever changing appearance for the pond. Functionally, they add to the oxygenators and produce varying casts of shadow that the pond owner and the fish will appreciate. Though in colder climates these plants are excellent choices, Giant Duck Weed (Spirodela oligorhiza), Water Hyacinth, and Water Lettuce are restricted plants in the state of Texas.