How much sun does Knotgrass need?

Knotgrass grows best in full sun conditions.

When does Knotgrass bloom?

Knotgrass blooms in June, July, August, and September.

Where is Knotgrass native?

Knotgrass (Paspalum distichum) is native to AL, AR, AZ, CA and 22 more states, per the USDA PLANTS Database and regional native plant society lists.

Is Knotgrass toxic to livestock?

The USDA PLANTS Database does not flag Knotgrass as toxic to livestock.

Is Knotgrass HOA-friendly?

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

Knotgrass

Name: Pollinator Patch
Author: Pollinator Patch

Paspalum distichum

Last reviewed: June 2026

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

Light

full sun

Water

high

Size

4"–24" H × 12"–36" W

Bloom

Jun, Jul, Aug, Sep

Native to

AL, AR, AZ, CA and 22 more states

Browse plants for this ecoregion

Coast Range Sierra Nevada Central California Valley Central California Foothills and Coastal Mountains Southern California Mountains Central Basin and Range Mojave Basin and Range Chihuahuan Deserts Central Oklahoma/Texas Plains Edwards Plateau Texas Blackland Prairies East Central Texas Plains Western Gulf Coastal Plain South Central Plains Sonoran Basin and Range

Knotgrass is a low-growing native perennial that spreads by runners to form dense mats. It produces small seed heads from summer through early fall and thrives in wet conditions. This grass is commonly found in marshy areas and along pond edges.

In an HOA neighborhood

Knotgrass 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.

Aggressive spreading habit can appear uncontrolled
High water requirements may conflict with water-wise landscaping preferences
Can develop patchy or weedy appearance

Wildlife value

The seed heads provide food for waterfowl and songbirds. As a native grass, it offers nesting material and habitat for small wildlife.

Common questions

How much sun does Knotgrass need?: Knotgrass grows best in full sun conditions.
When does Knotgrass bloom?: Knotgrass blooms in June, July, August, and September.
Where is Knotgrass native?: Knotgrass (Paspalum distichum) is native to AL, AR, AZ, CA and 22 more states, per the USDA PLANTS Database and regional native plant society lists.
Is Knotgrass toxic to livestock?: The USDA PLANTS Database does not flag Knotgrass as toxic to livestock.
Is Knotgrass HOA-friendly?: Knotgrass 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 USDA PLANTS Database and regional native plant society lists. Pollinator and host plant associations compiled from GBIF, iNaturalist, and published ecological literature.

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

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