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Cotton Grass

Eriophorum virginicum (er-ee-OH-for-um vir-JIN-ih-kum)

Family: Cyperaceae Native Herbaceous

This unique sedge, with flowers that look a bit like a shaving brush, is a perennial. It grows in bogs, wet meadows, and many other places with sun and damp or wet soil. It is one of many cottongrass (common name) cultivars with a flower that has a white to tan bristly appearing but soft, cotton like mass 1 to 2 inches across. Many cottongrass blooms are white but this one is often tawny (light brown) in color, hence one of its common names of Tawny cottongrass. It blooms from June to September. The flowers are perfect, meaning both male and female parts are present. The lowest 2 to 5 spikes of flowers each have a leaf-like bract (part between flower and stem) at the base of the stalk, of varying lengths, up to 5 or 6 inches long, and may be upward or downward pointing. The leaves are flat, grasslike and few in number, alternating on the stem. The leaves are simple, meaning that each is a single leaf attached to a stem or twig. This leaf is smooth and hairless. The sedge is densely clump forming and grows from spreading rhizomes under the soil. It is not common in NC but is native, in general, throughout the eastern half of the U.S. It is more commonly found in northern cooler states.

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 43 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
Ornamental Grasses and Sedges; Perennial
Life cycle
Perennial
USDA zones
3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a
Light
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
High Organic Matter; Loam (Silt)
Soil drainage
Moist | Occasionally Wet
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Maintenance
Low
Canopy layer
4 - Herbaceous
Form & Appearance
Habit / form
Clumping; Creeping; Spreading
Texture
Medium
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Alternate
Leaf shape
Linear
Leaf size
> 6 inches long, < 1 inch wide
Hairs present
No
Leaf detail
The smooth leaf is flat at the base with a short sheath and a total length of about 12 inches. The leaf can be round or triangular in cross section, about 4 mm wide.
Flower color
Cream/Tan; Green; White
Flower value
Long Bloom Season; Showy
Flower form
Spike
Flower size
1-3 inches
Bloom time
Summer
Fruit color
Black; Brown/Copper; White
Fruit size
< 1 inch long, < 1 inch wide
Fruit detail
Seeds are 4 mm or less in length.
Wildlife & Ecology
Native status
Native
Origin
E. Canada to N. Central & E. U.S.A.
Distribution
Widely in eastern US and Newfoundland
Food & Medicine
Harvest time
Summer
Landscape Use
Landscape location
Meadow; Pond; Riparian
Landscape theme
Rain Garden
Garden tags
#sedge #white flowers #wet soils tolerant #boggy sites #perennial #meadow #wildflower #wetland
Problems & Resistance
Resistant to
Wet Soil

Planted at Hunnicutt

Nobody’s planted this one yet.