Ray's Knotweed
Polygonum raii
- Native to:
- Canada, Denmark, France, Germany, Ireland, Poland, United States
Olivier Pichard
Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Polygonaceae
- Genus:
- Polygonum
- Species:
- Polygonum raii
- USDA Symbol:
- PORA6
Growth Characteristics
- Life Cycle:
- Annual | Perennial
- Growth Habit:
- Forb/herb
- Height:
- 100 cm
- Light Requirements:
- Full Sun
- Drought Tolerance:
- Low
- Bloom Months:
- jun,jul,aug,sep
- Bloom Colors:
- white, pink
Wildlife Benefits
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Host Plant for Caterpillars
Yellow-legged Tiger Moth (Haematopis grataria)
Garden & Ecology Notes
- Wildlife Value:
- birds
- Salt Tolerant:
- Yes
Soil Requirements
- Soil Type:
- sandy, nutrient-poor, well-drained soil
- pH:
- 6.0 - 7.5 (slightly acidic to neutral)
- Drainage:
- excellent drainage required
- Moisture:
- dry to moderate
- Notes:
- commonly found in coastal dunes
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–28 days
The above propagation data sourced from Claude AI