Prostrate Knotweed
Polygonum aviculare
Last reviewed: June 2026
Light
part shade
Water
low
Size
2"–12" H × 6"–24" W
Bloom
Jun, Jul, Aug, Sep
Native to
CO
Browse plants for this ecoregion
Prostrate knotweed is a low-growing annual that forms a spreading mat close to the ground. This hardy plant produces small, inconspicuous flowers from summer through early fall and tolerates poor soils and dry conditions.
In an HOA neighborhood
Prostrate 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.
- Commonly considered a weed
- Can spread aggressively
- Very informal appearance unsuitable for maintained landscapes
Wildlife value
This plant provides modest wildlife value, offering small seeds for birds and some nectar for small pollinators during its extended bloom period.
Common questions
- How much sun does Prostrate Knotweed need?
- Prostrate Knotweed grows best in part shade conditions.
- When does Prostrate Knotweed bloom?
- Prostrate Knotweed blooms in June, July, August, and September.
- Where is Prostrate Knotweed native?
- Prostrate Knotweed (Polygonum aviculare) is native to CO, per the USDA PLANTS Database and regional native plant society lists.
- Is Prostrate Knotweed HOA-friendly?
- Prostrate 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 Prostrate Knotweed? Add it to your garden in Pollinator Patch to track it and get season-by-season care guidance.
Not sure where to start? Take the 2-minute yard quiz