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Pale Knotweed

Persicaria lapathifolia

Last reviewed: June 2026

Pale Knotweed (Persicaria lapathifolia)
Photo: (c) Sandy Wolkenberg, some rights reserved (CC BY), uploaded by Sandy Wolkenberg

Light

part shade

Water

medium

Size

12"–36" H × 6"–24" W

Bloom

Jun, Jul, Aug, Sep

Native to

MT

Pollinators

bees, beetles

Browse plants for this ecoregion

Coast RangeSierra NevadaCentral California ValleyCentral California Foothills and Coastal MountainsSouthern California/Northern Baja CoastCentral Basin and RangeMojave Basin and RangeChihuahuan DesertsCentral Oklahoma/Texas PlainsEdwards PlateauEast Central Texas PlainsSouth Central PlainsSonoran Basin and Range

Pale knotweed is an annual wildflower that produces small pink or white flower clusters from summer through fall. This native plant grows in a somewhat sprawling habit and thrives in partially shaded areas with moderate moisture.

In an HOA neighborhood

Pale 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.

  • Has a weedy, unkempt appearance
  • Annual habit means gaps in landscape design
  • Common name includes 'weed' which raises HOA concerns

Wildlife value

The long blooming period from June through September provides nectar for bees and beetles throughout the growing season.

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

See it in the app

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