Potamogeton crispus (Curly Pondweed) is a submerged aquatic perennial with stems up to 3-4 ft. long (90-120 cm) bearing narrowly lance-shaped, stiff, translucent, light to dark-green leaves, 1.5-4 in. long (4-10 cm), with strongly curly margins. The plant is either entirely submersed or nearly entirely submersed with some leaves floating at the surface. Inconspicuous, tiny reddish flowers bloom in summer to early fall. They give way to flat seeds with a pointed beak, which do not seem to be viable. Curly Pondweed reproduces mainly vegetatively via rhizomatic spread as well as with turions. Turions or short, densely-leaved resistant stems, break dormancy in the fall, survive the winter, then grow rapidly in early spring when water temperatures are still quite cool. Curly Pondweed provides habitat for aquatic life when native plants are not present in the winter and early spring. Native to Africa, temperate and tropical Asia, Australasia, Europe, Curly Pondweed tolerates fresh or slightly brackish water and can grow in shallow, deep, still or flowing water. It is a common water garden or aquarium plant which is useful as an oxygenator and provides a shelter for small fishes and aquatic invertebrates. However, its growth habit allows the plant to begin growing in the spring before native plant species, outcompeting them for light and space early in the growing season. As a result, Curly Pondweed tends to reduce plant diversity by forming monocultures. It is invasive in temperate areas of North America, New Zealand, and southern South America, and is listed as a noxious or prohibited weed in several areas of the USA. Before planting outdoors, gardeners should contact their local department of fish and wildlife for more information on invasive species and noxious weeds.

• Grows up to 2-4 in. tall (5-10 cm) and 3-5 feet. wide (90-150 cm).
• Performs best in full sun to part shade in baskets of sandy loam in the bottom mud of the pond.
• No serious pest or disease issues.
• Thin on a regular basis to keep in check.
• Native to Africa, temperate and tropical Asia, Australasia, Europe.
• Find where Potamogeton crispus is invasive in the U.S.