The European Water Plantain is an aquatic perennial in the water plantain family (Alismataceae). It is native to northern temperate regions of Europe, Asia, and northern and central Africa. The plant is found on mud, in lakes, rivers, ditches, ponds, and grazed shores in its native environment. The genus name is the Celtic word for water. The plant grows 2-3 feet tall and about 18 inches wide. The plant prefers full sun and wet, poorly-drained soil. It will survive in 12-18 inches of water and containers of water. Self-seeding can be a problem if the flowers are not deadheaded. Propagation is by rhizome division in spring or seed. The tiny white to pale pink flowers are very fragrant and bloom late spring and summer in whorls on long stems. The flowers attract bees and flies. The fruit is eaten by wildlife. The foliage may cause skin irritation. The common name, Mad-Dog Weed, refers to its medicinal use to treat rabies. There are few commercial nurseries in the United States that sell it. The leaves and roots are edible but must be boiled or dried to destroy its toxic ingredient. Grow this aquatic plant in marshy areas, ponds, bogs, and wet areas. Insects, Diseases, and Other Plant Problems: No serious pest or disease. The plant can be weedy and spread via self-seeding. Slugs are attracted to the plant.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0); Neutral (6.0-8.0)
Soil drainage
Frequent Standing Water
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 3 ft. 0 in. | Width: 1 ft. 0 in. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
High
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Clumping; Erect; Spreading
Texture
Fine
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Whorled
Leaf shape
Linear; Oblong; Ovate
Leaf margin
Entire
Leaf size
> 6 inches long, 3-6 inches wide
Hairs present
No
Leaf detail
The basal rosette leaves are grey-green and up to 12 inches long. Blades are ovate with rounded or cordate bases and an occasional splash of purple. Submerged leaves may be strap-like.
Flower color
Pink; Purple/Lavender; White
Flower value
Fragrant; Long Bloom Season
Flower form
Panicle; Raceme
Flower shape
Saucer
Flower size
< 1 inch
Flower detail
Three round or slightly jagged, white, pink pale or purple petals. The flowers open in the afternoon from June-September. There are 3 blunt green sepals, and 6 stamens per flower. Flowers in whorled groups forming a narrowing (cone-like) raceme.
Bloom time
Spring; Summer
Fruit type
Achene
Fruit detail
The ripe achenes may float for several days dispersing long distances.