Limnobium spongia (American Frogbit)

Limnobium spongia (American Frogbit) is a floating, aquatic perennial forming loose rosettes of thick and leathery, rounded or somewhat heart-shaped leaves, 1-3 in. across (2-7 cm). The younger leaves tend to be glossy bright green above and reddish underneath. American Frogbit can freely float on water or root itself in mud. Tiny inconspicuous white flowers are produced in summer and fall. The root system is fibrous and stoloniferous. American Frogbit can spread aggressively in warm climates by means of its stolons. In the northern part of its range, American Frogbit overwinters as dormant turions sink to the ground until spring, while in warmer climates it can grow throughout the year. Native to the eastern United States, American Frogbit occurs naturally in swamps, the water of lakes and ponds, muddy borders of lakes and ponds, and deep ditches. American Frogbit is a popular addition to water gardens and ponds, where it provides attractive foliage cover and discourages algae growth. Its succulent leaves are eaten by turtles while its fruits and seeds are eaten by waterfowl.

• Grows up to 1-2 in. tall (2-5 cm). 
• Performs best in full sun to part shade on still or very slow-moving water in water gardens, ponds or aquatic containers.
• Virtually pest and disease free. Keep an eye out for Cercospora limnobii, a fungal disease that can cause brown lesions to develop on the leaf blades.
• Reduce its spread by removing portions with a net.
• Native to the eastern United States.
• Find where this species is invasive in the U.S.