American Mannagrass
Glyceria grandis
Last reviewed: June 2026
Light
part sun
Water
high
Size
24"–60" H × 12"–24" W
Bloom
Jun, Jul, Aug
Native to
AZ, CA, CO, CT and 33 more states
Browse plants for this ecoregion
American mannagrass is a tall native wetland grass that forms upright clumps with narrow green leaves. It produces delicate seed heads in summer and thrives in consistently moist to wet soils.
In an HOA neighborhood
American Mannagrass 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.
- Requires consistently wet conditions that may create drainage concerns
- Can appear wild and unkempt compared to typical landscape grasses
- May spread aggressively in suitable wet conditions
Wildlife value
The seeds provide food for waterfowl and songbirds, while the dense clumps offer nesting habitat for wetland birds.
Native range data from the USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.
Does American Mannagrass fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.