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Purple Wen-dock

Brasenia schreberi (brah-SEE-nee-uh shre-BER-ee)

Family: Cabombaceae Native Herbaceous

Water Shield is an herbaceous perennial, aquatic, native plant with long, slender, branching stems. It resembles water lilies ( Nymphaeaceae ) because both are found submerged or floating on the water's surface. Water Shield, in particular, is found in nature on ponds, lakes, and sluggish streams throughout the world. It has creeping, thin rhizomes rooted in the mud at the bottom of ponds, floating leaves, and grows in a wide range of water depths (1 inch to 6 feet). It does best on the water edge in 8 to 10 inches of water, but with the roots planted in the mud of more shallow waters. The young leaf tips, which are coated with a thick transparent mucilage, are eaten in salad with vinegar, sake and soy sauce, or added to soups as a thickener. The plant is considered a delicacy in Japan where it is often bottled and sold in local markets. The species name, schreberi , is for Johann Christian Daniel von Schreber, a German botanist and student of Linnaeus in the 18th century. Water Shield has properties that inhibit the growth of other plants nearby. Thus, the plant can become dominant and provide a natural control of invasive water weeds. Water Shield is pollinated by the wind in a very unusual process. Individual flowers are open for a two-day period. On the first day the flower is open it is functionally female, with the stigmas receptive to pollen. At the end of the first day the flower is drawn below the water’s surface. On the second day the flower again extends above the water’s surface and the anthers release their pollen. The flower is then pulled below the water’s surface again and the fruit develop. Diseases, Insect Pests. and Other Plant Problems: No known diseases or insect pests. Water Shield is often considered a pest as its dense growth interferes with fishing, swimming, and boating.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 45 attributes.

How it fits the guild

Guild layer 4 - Herbaceous
See companions & conflicts ↓

Companions & Conflicts

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 plant profile

Growing Conditions
Plant type
Herbaceous Perennial; Native Plant; Water Plant
Life cycle
Perennial
Light
Full sun (6 or more hours of direct sunlight a day)
Soil drainage
Frequent Standing Water
NC region
Coastal; Mountains; Piedmont
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Creeping; Multi-stemmed; Spreading
Texture
Medium
Leaf color
Green; Purple/Lavender
Leaf arrangement
Alternate
Leaf shape
Elliptical; Ovate
Leaf margin
Entire
Leaf feel
Slippery
Leaf size
1-3 inches long, < 1 inch wide
Hairs present
No
Leaf detail
This plant has floating oval leaves (2 1/2 inches long and half as wide) borne on long petioles. The underside of leaves has a gelatinous coating. The Leaves are oval to elliptic in shape, green above, often purple beneath, long-stemmed, and have the stalk or petiole attached to the lower surface instead of the base or edge.
Flower color
Gold/Yellow; Pink; Purple/Lavender; Red/Burgundy
Flower form
Solitary
Flower size
< 1 inch
Flower detail
This plant has purple to red, 3-petaled, 1/2 inch flowers on the water surface. Flowers close at night. The flowers have sepals and petals that are similar to each other.
Bloom time
Fall; Summer
Fruit type
Achene
Fruit detail
Each fertilized pistil develops into a 1 or 2 seeded hard, ellipsoid or fusiform fruit. The style persists on the fruit. The fruit does not split open to release the seed.
Stem color
Brown/Copper
Stem detail
Underside of leaf and stem have a gel-like coating.
Wildlife & Ecology
Native status
Native
Origin
Africa, Temperate and Subtropical Asia, East Australia, America
Distribution
North America from Nova Scotia to Manitoba and Nebraska, south to Florida, Texas and Mexico.
Wildlife value
The fruit are eaten by water fowl.
Food & Medicine
Edible parts
Leaves
Harvest time
Fall; Summer
Fruit type
Achene

Edibility

Leaves are eaten in salad or used as a thickener in soups.

Landscape Use
Landscape location
Pond
Landscape theme
Native Garden; Water Garden
Garden tags
#purple #water garden #purple flowers #red flowers #NC native #Coastal OBL #food source summer #Piedmont Mountains OBL #food source fall #Audubon #food source hard mast fruit #rhizomes #wildlife friendly #NC Native Pollinator Plant
Problems & Resistance
Propagation
Division; Seed

Planted at Hunnicutt

Nobody’s planted this one yet.