Water lilies help provide shade and keep water temperatures cool. These floating plants keep algae growth down but may end up completely covering a shallow pond.
Also known as nymphaea, the water lily is a floating plant found in environments from desert to tropical to temperate, all around the world. Gardeners can find these plants in a variety of colors and sizes. Some varieties grow to over 25 square feet. In climates with cold winters, hardy lilies go dormant and bloom again from late spring to fall. Tropical varieties require warmer temperatures, at least 80 degrees Fahrenheit, to start blooming. They usually do not survive the winter.