The exotic limnophila has submersed and emersed leaves and stems. It
can grow in a variety of aquatic habitats.
The stems of limnophila can grow to 12 feet long, with a few inches being
emersed above the water. The emersed leaves of limnophila are in whorls
and are more-or-less lance-shaped. The emersed leaf margins appear to
be torn irregularly. The submersed leaves are very different looking,
being finely divided and feathery, about one inch long, and in whorls
about the stem. Limnophila flowers are not common. They are blue, violet,
pink, or lavender. Single flowers grow on the emersed part of the stem.
Limnophila sessiliflora is a freshwater aquatic herb with submersed and emersed stems up to 4 m long. Introduced to and currently sold in the U.S. as an aquarium plant. Its stems form dense stands, clogging canals and pumping and power stations in Florida. It is a major weed of rice fields in Asia. Fast growing, it reproduces by both seeds and stem fragments. L. sessiliflora is resistant to chemical control and is reported to outcompete Hydrilla.