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Common Duckmeat

Spirodela polyrhiza (spy-roh-DEL-uh pol-ee-RY-za)

Family: Araceae Native Herbaceous

Greater Duckweed is a perennial aquatic plant found in slow-moving or still waters of ponds, bogs, lakes, and swamps all over the world. Nitrogen and other nutrients will be common to these waters. Protection from wind and waves is crucial to the plants survival. Growing on the water surface, this simple, oval-shaped life form consists of a single, flat thallus, which is a plant that combines the functions of both the leaf and the stem. Each tiny (.35" x .27") thallus is filled with even smaller pockets of air that give it floating capabilities. The upper side of the thallus is a medium green, while the underside is typically a reddish-purple. A single, red node is located on the upper side. Each node can have 5-12 veins that curve inward. These are not visible to the naked eye. Although rare to bloom, flowers are produced from 2 pouches on the thallus. One pouch will contain a single female flower with a single pistil, the other will contain 2 male flowers that contain a single stamen. The female flower is replaced by a tiny fruit in the form of a sack which has 1 to 2 seeds. In lieu of flowering, the thallus can produce buds that are attached to the mother plant for a period of time before separating into individual plants. Its roots are a group of tiny rootlets coming from a node on the underside of the thallus. Winter and cooler weather cause the thallus to form a starchy off-set called a winter turion. Bud-like in form, and brown to olive green, the turion will detach from the mother plant and sink to the bottom of the water. As spring approaches, it will rise to the surface. While this plant is a food source for some aquatic mammals such as ducks and turtles, it also provides a habitat for aquatic organisms. Due to its metabolically active cells and little structure fibers, its tissue has two times the protein, fat, nitrogen and phosphorus plants, giving the plant a high nutritional value. Insects, Diseases, and Other Plant Problems: Its rapid growth can cause this plant to spread agressively. It also spreads by mammals such as beavers and muskrats that spread this plant from one wetland to another when the sticky roots attach to their wet fur.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 40 attributes.

How it fits the guild

Guild layer 4 - Herbaceous Optimal soil pH Neutral (6.0-8.0)
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
USDA zones
5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Neutral (6.0-8.0)
Soil drainage
Occasionally Wet
Available space
Less than 12 inches
NC region
Coastal
Growth rate
Rapid
Maintenance
Medium
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Horizontal
Texture
Medium
Hairs present
No
Leaf detail
No leaves.
Flower form
Spadix
Flower size
< 1 inch
Flower detail
Blooms (rarely) from June into the fall.
Bloom time
Fall; Summer
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
The fruits form as a sack and contain 1 to 2 seeds.
Stem detail
No stems.
Wildlife & Ecology
Native status
Native
Origin
Worldwide
Wildlife value
Several aquatic mammals feed on this plant. Ducks, turtles, and fish are among these.
Attracts
Songbirds
Play value
Wildlife Cover/Habitat; Wildlife Food Source
Food & Medicine

Uses (ethnobotany)

Terrariums

Landscape Use
Landscape location
Pond
Landscape theme
Native Garden; Rain Garden; Water Garden
Garden tags
#swamps #Piedmont Mountains OBL #Coastal OBL #food source herbage #Audubon #spadix #aquatic #succulent #mat forming #water garden #shade intolerant #fast growing #aggressive #boggy sites #perennial #colonizing #wildlife friendly #NC native #weedy #pond #wetland
Problems & Resistance
Problems
Weedy

Planted at Hunnicutt

Nobody’s planted this one yet.