How much sun does Thinleaf Cottonsedge need?

Thinleaf Cottonsedge grows best in part sun conditions.

When does Thinleaf Cottonsedge bloom?

Thinleaf Cottonsedge blooms in May, June, and July.

Where is Thinleaf Cottonsedge native?

Thinleaf Cottonsedge (Eriophorum viridicarinatum) is native to CO, CT, IA, ID and 15 more states, per the World Checklist of Vascular Plants (Kew).

What pollinators does Thinleaf Cottonsedge attract?

Thinleaf Cottonsedge draws bees and flies.

Is Thinleaf Cottonsedge HOA-friendly?

Thinleaf Cottonsedge takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Thinleaf Cottonsedge

Name: Pollinator Patch
Author: Pollinator Patch

Eriophorum viridicarinatum

Last reviewed: August 2026

Toxicity unknown

Thinleaf Cottonsedge (Eriophorum viridicarinatum) is not listed by the ASPCA Animal Poison Control Center (opens in new tab) or the other sources we check, so we have no verdict for it either way. Absence from those lists is not a clearance. If your pet shows symptoms after eating any plant, call the ASPCA at (888) 426-4435.

Light

part sun

Water

high

Size

8"–24" H × 6"–12" W

Bloom

May, Jun, Jul

Native to

CO, CT, IA, ID and 15 more states

Pollinators

bees, flies

Before you buy

Your city may pay you to plant this

Cities and water utilities offer rebates for replacing lawn with native and water-wise plants. We track 445 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Browse plants for this ecoregion

Northern Forests Northern Lakes and Forests North Central Hardwood Forests Driftless Area Southeastern Wisconsin Till Plains Eastern Corn Belt Plains Southern Michigan/Northern Indiana Drift Plains Northeastern Highlands Northeastern Coastal Zone Northern Allegheny Plateau Ridge and Valley Acadian Plains and Hills Eastern Great Lakes Lowlands

Thinleaf cottonsedge is a native wetland perennial that forms small clumps of narrow, grass-like foliage. It produces distinctive white, fluffy seed heads from late spring through summer that give it its common name. This plant thrives in consistently moist to wet soils and partial sun conditions.

In an HOA neighborhood

Thinleaf Cottonsedge takes more care to keep looking intentional in a front yard. Maintenance level: moderate. Consider it for backyard or mid-zone beds rather than the street edge.

Works well in: backyard only.

Looks wild and unmanicured even when healthy
Requires constantly wet soil that may be impractical in typical landscapes
Fluffy seed heads can appear messy to some

Wildlife value

The flowers attract bees and flies during its May through July bloom period. The fluffy seed heads provide material for bird nesting and the plant offers habitat for wetland-associated wildlife.

Common questions

How much sun does Thinleaf Cottonsedge need?: Thinleaf Cottonsedge grows best in part sun conditions.
When does Thinleaf Cottonsedge bloom?: Thinleaf Cottonsedge blooms in May, June, and July.
Where is Thinleaf Cottonsedge native?: Thinleaf Cottonsedge (Eriophorum viridicarinatum) is native to CO, CT, IA, ID and 15 more states, per the World Checklist of Vascular Plants (Kew).
What pollinators does Thinleaf Cottonsedge attract?: Thinleaf Cottonsedge draws bees and flies.
Is Thinleaf Cottonsedge HOA-friendly?: Thinleaf Cottonsedge takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

Native range data from the World Checklist of Vascular Plants (Kew). Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

Ready to grow Thinleaf Cottonsedge? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

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