Rosebay Willowherb
Chamerion angustifolium
Last reviewed: June 2026
Light
part shade
Water
medium
Size
24"–72" H × 12"–36" W
Bloom
Jun, Jul, Aug, Sep
Native to
RI
Pollinators
bees, butterflies, moths
Browse plants for this ecoregion
Rosebay willowherb is a tall perennial wildflower that produces spikes of bright pink-purple flowers from summer into early fall. This native plant can reach up to 6 feet tall and spreads readily through underground rhizomes and wind-dispersed seeds. It thrives in partial shade with moderate moisture and dies back completely in winter.
In an HOA neighborhood
Rosebay Willowherb 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.
- Can spread aggressively and look wild or weedy
- Tall growth habit may appear uncontrolled
- Dies back completely in winter leaving bare stems
Wildlife value
The long blooming period provides nectar for bees, butterflies, and moths throughout the summer and fall. Seeds are an important food source for birds, and the plant serves as a host for several moth species.
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 Rosebay Willowherb fit your yard? Open it in Pollinator Patch to check it against your sun, soil, and HOA-conscious filters.