How much sun does Pale Knotweed need?

Pale Knotweed grows best in part shade conditions.

When does Pale Knotweed bloom?

Pale Knotweed blooms in June, July, August, and September.

Where is Pale Knotweed native?

Pale Knotweed (Persicaria lapathifolia) is native to AL, AR, CA, CO and 40 more states, per the USDA PLANTS Database and regional native plant society lists.

What pollinators does Pale Knotweed attract?

Pale Knotweed draws bees and beetles.

Is Pale Knotweed HOA-friendly?

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

Pale Knotweed

Name: Pollinator Patch
Author: Pollinator Patch

Persicaria lapathifolia

Last reviewed: July 2026

Light

part shade

Water

medium

Size

12"–36" H × 6"–24" W

Bloom

Jun, Jul, Aug, Sep

Native to

AL, AR, CA, CO and 40 more states

Pollinators

bees, beetles

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 East Central Texas Plains South Central Plains Sonoran 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.

Common questions

How much sun does Pale Knotweed need?: Pale Knotweed grows best in part shade conditions.
When does Pale Knotweed bloom?: Pale Knotweed blooms in June, July, August, and September.
Where is Pale Knotweed native?: Pale Knotweed (Persicaria lapathifolia) is native to AL, AR, CA, CO and 40 more states, per the USDA PLANTS Database and regional native plant society lists.
What pollinators does Pale Knotweed attract?: Pale Knotweed draws bees and beetles.
Is Pale Knotweed HOA-friendly?: Pale 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 Pale Knotweed? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.

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