How much sun does Denseflower Knotweed need?

Denseflower Knotweed grows best in part sun conditions.

When does Denseflower Knotweed bloom?

Denseflower Knotweed blooms in July, August, and September.

Where is Denseflower Knotweed native?

Denseflower Knotweed (Persicaria glabra) is native to AL, AR, DE, FL and 13 more states, per the USDA PLANTS Database and regional native plant society lists.

What pollinators does Denseflower Knotweed attract?

Denseflower Knotweed draws bees and beetles.

Is Denseflower Knotweed HOA-friendly?

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

Denseflower Knotweed

Name: Pollinator Patch
Author: Pollinator Patch

Persicaria glabra

Last reviewed: June 2026

Light

part sun

Water

medium

Size

12"–36" H × 6"–18" W

Bloom

Jul, Aug, Sep

Native to

AL, AR, DE, FL and 13 more states

Pollinators

bees, beetles

Browse plants for this ecoregion

Central Oklahoma/Texas Plains Texas Blackland Prairies East Central Texas Plains Western Gulf Coastal Plain South Central Plains

Persicaria glabra is a native perennial that produces dense clusters of small white to pink flowers from summer through early fall. This compact plant forms neat clumps and thrives in partial sun with average moisture conditions.

In an HOA neighborhood

Denseflower Knotweed 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.

Name contains 'knotweed' which has negative associations
May be confused with invasive knotweed species
Relatively unknown plant may raise HOA concerns

Wildlife value

The dense flower clusters attract bees and beetles during the long blooming period from July through September.

Common questions

How much sun does Denseflower Knotweed need?: Denseflower Knotweed grows best in part sun conditions.
When does Denseflower Knotweed bloom?: Denseflower Knotweed blooms in July, August, and September.
Where is Denseflower Knotweed native?: Denseflower Knotweed (Persicaria glabra) is native to AL, AR, DE, FL and 13 more states, per the USDA PLANTS Database and regional native plant society lists.
What pollinators does Denseflower Knotweed attract?: Denseflower Knotweed draws bees and beetles.
Is Denseflower Knotweed HOA-friendly?: Denseflower Knotweed 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 Denseflower Knotweed? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

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