Elodea canadensis

Species Native to Missouri
Common Name: Canadian pondweed 
Type: Herbaceous perennial
Family: Hydrocharitaceae
Native Range: North America
Zone: 4 to 10
Height: 0.25 to 0.25 feet
Spread: 1.00 to 3.00 feet
Bloom Time: July to September
Bloom Description: Greenish-white
Sun: Full sun
Water: Wet
Maintenance: Medium
Suggested Use: Water Plant, Naturalize, Rain Garden
Flower: Insignificant

Culture

Easily grown as a submerged aquatic, either anchored or free-floating, in water gardens in full sun. Thrives in cool water. Set plants out in pots or containers at the bottom of the water body or float plant cuttings/fragments in the water. Plant roots may be anchored in the muddy bottoms of small ponds. Remove or clip stems as needed to control population. Plants often remain green in winter and will overwinter under a cover of ice. Plants spread rapidly and can take over larger bodies of water, but are relatively easy to control in small water gardens.

Noteworthy Characteristics

Elodea canadensis, commonly called Canadian pondweed, is a submerged aquatic perennial that has become a popular plant for water gardens and cool water aquariums. By absorbing nutrients, it helps control algae and keep waters clear. It produces fragile, branching, tangled stems to 3.5’ long (10-12’ in the wild) densely clad with short, drooping, lance-shaped to ovate dark green leaves (to 5/8” long) in whorls of three. Tiny, apetalous greenish-white flowers appear from July to September. Plants are dioecious with male and female flowers appearing on separate plants. Male flowers are rare, so propagation more often takes place by stem fragmentation than sexually. When pollination does occur, it is waterborne (pollen drifts from male to female flowers). Plants also produce buds (turions) which sink to the bottom in fall, overwinter as dormant buds and produce new plants in spring. Colonies in the wild provide excellent cover for fish, small crustaceans, insect larvae and snails. Native to North America, but widely naturalized in Europe. Synonymous with and formerly known as Anacharis canadensis. Also commonly called waterweed or anacharis. This plant is sometimes sold in small bunches for large aquariums where it provides interesting foliage and serves as both an oxygenator and water clarifier, although its close relative, Egeria densa (Brazilian waterweed marketed under the name of anacharis), is more commonly sold for this purpose.

Genus name comes from the Greek word helodes meaning marshy or bred in marshes.

Specific epithet means of Canada.

Problems

No serious insect or disease problems.

Garden Uses

Water gardens. Not recommended for large ponds where population control can be more difficult. Large aquariums.