How much sun does Marsh Arrow-grass need?

Marsh Arrow-grass grows best in full sun conditions.

When does Marsh Arrow-grass bloom?

Marsh Arrow-grass blooms in May, June, July, August, and September.

Where is Marsh Arrow-grass native?

Marsh Arrow-grass (Triglochin palustris) is native to AZ, CA, CO, IA and 22 more states, per the World Checklist of Vascular Plants (Kew).

Is Marsh Arrow-grass HOA-friendly?

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

Marsh Arrow-grass

Name: Pollinator Patch
Author: Pollinator Patch

Triglochin palustris

Last reviewed: August 2026

Toxicity unknown

Marsh Arrow-grass (Triglochin palustris) 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

full sun

Water

high

Size

4"–16" H × 2"–8" W

Bloom

May, Jun, Jul, Aug, Sep

Native to

AZ, CA, CO, IA and 22 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

Browse plants for this ecoregion

Sierra Nevada North American Deserts Central Basin and Range Northwestern Forested Mountains Southern Rockies Arizona/New Mexico Mountains High Plains Northwestern Glaciated Plains Northern Glaciated Plains Western Corn Belt Plains Great Plains Northern Forests Northern Lakes and Forests North Central Hardwood Forests Southeastern Wisconsin Till Plains Eastern Corn Belt Plains Southern Michigan/Northern Indiana Drift Plains Eastern Great Lakes Lowlands

Marsh arrow-grass is a slender wetland perennial with narrow, grass-like leaves that forms small clumps in consistently moist to wet soils. It produces inconspicuous spikes of tiny greenish flowers from late spring through early fall. This plant thrives in full sun and requires constant moisture, making it ideal for rain gardens or bog areas.

In an HOA neighborhood

Marsh Arrow-grass 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.

Requires constantly wet conditions that may create drainage concerns
Grass-like appearance could be mistaken for unmaintained turf
Inconspicuous flowers provide little ornamental appeal

Wildlife value

While specific pollinator data is limited, this native wetland plant likely provides habitat value for moisture-loving insects and small wildlife. Its seeds may provide food for waterfowl and wetland birds.

Common questions

How much sun does Marsh Arrow-grass need?: Marsh Arrow-grass grows best in full sun conditions.
When does Marsh Arrow-grass bloom?: Marsh Arrow-grass blooms in May, June, July, August, and September.
Where is Marsh Arrow-grass native?: Marsh Arrow-grass (Triglochin palustris) is native to AZ, CA, CO, IA and 22 more states, per the World Checklist of Vascular Plants (Kew).
Is Marsh Arrow-grass HOA-friendly?: Marsh Arrow-grass 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.

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 Marsh Arrow-grass? 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