knotweed
Persicaria virginiana
USDA zones4 to 8
SunHandles full sun to partial shade
WaterHandles moderate to wet soil
Size2 to 3 feet tall3 to 4 feet wide
- Growth rate
- Rapid
- Habit
- Arching
- Bloom season
- Spring, summer, autumn
- Bloom color
- White to greenish-white, rarely pink
- Foliage color
- Green
- Soil types
- Sand, loam, clay, chalk
- Soil pH
- Acid, alkaline, neutral
Garden uses
Attracts
Notes
Knotweed (Persicaria virginiana) is a perennial for borders, shade gardens, and naturalized areas. It is hardy to USDA zone 4, or down to -30°F (-34°C). This plant likes full sun to part shade and average to wet soil of most types. White to greenish-white flowers attract butterflies and bees. Deer rarely make it their first choice. Give it room, since this fast grower has arching stems that spread up to 48 inches wide.
Pairs well with New England aster, Woodland phlox, and Big bluestem.
Native range
Japan, Himalayas, and northeastern United States.