When does Tall Mannagrass bloom?

Tall Mannagrass typically flowers from June through August, producing loose, drooping seed heads on tall stems.

How much water does Tall Mannagrass need?

This grass prefers consistently wet to moist soil and does best in streamside, seep, or wet meadow conditions rather than dry sites.

How much sun does Tall Mannagrass need?

It grows well in part sun and tolerates a range of light from fuller sun near water to partial shade under an open canopy.

What growing conditions suit Tall Mannagrass best?

It thrives in cool, moist mountain habitats such as stream edges, wet meadows, and seasonally saturated soils at moderate to higher elevations.

Is Tall Mannagrass HOA-friendly?

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

Tall Mannagrass

Name: Pollinator Patch
Author: Pollinator Patch

Glyceria elata

Last reviewed: August 2026

Tall mannagrass is a moisture-loving grass found along streambanks and wet meadows in mountain regions of the western United States, blooming from June through August.

Toxicity unknown

Tall Mannagrass (Glyceria elata) 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

24"–60" H × 12"–24" W

Bloom

Jun, Jul, Aug

Native to

AZ, CA, CO, ID and 7 more states

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Browse plants for this ecoregion

Coast Range Puget Lowland Marine West Coast Forest Northwestern Forested Mountains Sierra Nevada Central California Foothills and Coastal Mountains Southern California Mountains North American Deserts Central Basin and Range Southern Rockies Arizona/New Mexico Mountains Madrean Archipelago

Glyceria elata is a tall native wetland grass that forms upright clumps with graceful seed heads in summer. This moisture-loving perennial thrives in wet soils and partial sun conditions. It provides natural movement and texture to water features or consistently moist garden areas.

Growing Tall Mannagrass

Grow Tall Mannagrass in part sun and high water. Mature plants reach 24 to 60 inches tall and spread 12 to 24 inches wide. Expect high maintenance to keep it looking intentional in a front yard.

In an HOA neighborhood

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

Works well in: backyard only.

Very tall height appears weedy in formal settings
Requires consistently wet soil which creates maintenance challenges
Informal wetland appearance conflicts with typical landscaping expectations

Wildlife value

The seeds provide food for waterfowl and songbirds, while the dense clumps offer nesting habitat for marsh birds. The grass structure supports beneficial insects and creates cover for small wildlife.

Common questions

When does Tall Mannagrass bloom?: Tall Mannagrass typically flowers from June through August, producing loose, drooping seed heads on tall stems.
How much water does Tall Mannagrass need?: This grass prefers consistently wet to moist soil and does best in streamside, seep, or wet meadow conditions rather than dry sites.
How much sun does Tall Mannagrass need?: It grows well in part sun and tolerates a range of light from fuller sun near water to partial shade under an open canopy.
What growing conditions suit Tall Mannagrass best?: It thrives in cool, moist mountain habitats such as stream edges, wet meadows, and seasonally saturated soils at moderate to higher elevations.
Is Tall Mannagrass HOA-friendly?: Tall Mannagrass 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.

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