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Denseflower Knotweed

Persicaria glabra

Last reviewed: June 2026

Denseflower Knotweed (Persicaria glabra)
Photo: Vinayaraj / Wikimedia Commons (CC BY-SA 3.0)

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

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.

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 Denseflower Knotweed fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.