What growing conditions does Carex intumescens need?

This sedge does best in part shade with consistently moist to wet soil, the kind found along stream banks, swamp edges, and low woodland spots.

When does Carex intumescens bloom?

It flowers from May into July, producing the inflated, papery seed sacs that give this species its common name, greater bladder sedge.

Is Carex intumescens a good choice for a rain garden or wet shade area?

Yes, its preference for high moisture and part shade makes it well suited to rain gardens, pond edges, and other consistently damp, shaded planting beds.

Does Carex intumescens have showy flowers?

No, the flowers are inconspicuous. The main visual interest comes later from the swollen, bladder-like fruiting bodies rather than the bloom itself.

Is Greater Bladder Sedge toxic to livestock?

The USDA PLANTS Database does not flag Greater Bladder Sedge as toxic to livestock.

Is Greater Bladder Sedge HOA-friendly?

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

Greater Bladder Sedge

Name: Pollinator Patch
Author: Pollinator Patch

Carex intumescens

Last reviewed: August 2026

Carex intumescens is a clump-forming sedge of wet woods and swamp margins, blooming from May through July with inflated, bladder-like fruits that stand out in shaded, moist sites.

Toxicity unknown

Greater Bladder Sedge (Carex intumescens) 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.

The USDA PLANTS Database (opens in new tab) does not flag Greater Bladder Sedge as toxic to livestock.

Light

part shade

Water

high

Size

12"–36" H × 6"–18" W

Bloom

May, Jun, Jul

Native to

AL, AR, CT, DE and 30 more states

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 452 programs across 44 states, each with a link to the provider and the date we last checked it.

Find rebates in your area

Greater bladder sedge is a native wetland grass that forms clumps of arching green foliage. It thrives in consistently moist to wet soils and produces small, inconspicuous flowers from late spring through summer.

Growing Greater Bladder Sedge

Grow Greater Bladder Sedge in part shade and high water. Mature plants reach 12 to 36 inches tall and spread 6 to 18 inches wide. Expect low maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

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

Works well in: backyard only.

Has a distinctly wild, wetland appearance
Seed heads can look unkempt to traditional gardeners
Associated with swampy areas rather than maintained landscapes

Wildlife value

This sedge provides nesting material and shelter for birds, while its seeds feed waterfowl and songbirds. The dense clumps offer habitat for beneficial insects and small wildlife.

Common questions

What growing conditions does Carex intumescens need?: This sedge does best in part shade with consistently moist to wet soil, the kind found along stream banks, swamp edges, and low woodland spots.
When does Carex intumescens bloom?: It flowers from May into July, producing the inflated, papery seed sacs that give this species its common name, greater bladder sedge.
Is Carex intumescens a good choice for a rain garden or wet shade area?: Yes, its preference for high moisture and part shade makes it well suited to rain gardens, pond edges, and other consistently damp, shaded planting beds.
Does Carex intumescens have showy flowers?: No, the flowers are inconspicuous. The main visual interest comes later from the swollen, bladder-like fruiting bodies rather than the bloom itself.
Is Greater Bladder Sedge toxic to livestock?: The USDA PLANTS Database does not flag Greater Bladder Sedge as toxic to livestock.
Is Greater Bladder Sedge HOA-friendly?: Greater Bladder Sedge takes more care to look intentional in a front yard. Consider it for backyard or mid-zone beds rather than the street edge.

These answers were drafted with an AI model from this plant's data. Verify care details with a local expert.

Native range data from vouchered herbarium specimen records and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

If something looks wrong

Common plant problems, and what to check first

These come up on almost any plant. Each guide lists the likely causes in the order they are worth ruling out, with one thing to check before you act on any of them, and links to the source it came from.

See all plant problem guides

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

Add this plant to your garden

iPhone app Android app

Planning a bed around it? Start a free plan with this plant

Not sure where to start? Take the 2-minute yard quiz