North American native vervain with candelabra spikes of small blue-violet flowers. Nervine and digestive with a bitter taste.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 3–8 | −40 °C to −6.7 °C | Plant tolerates down to this zone |
| RHS hardiness rating | H7 | down to −20 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 3–8 | −34 °C to −1 °C | Plant tolerates down to this zone |
| Australian (ANBG) zone | Zone 1–4 | −15 °C to 5 °C | Plant tolerates down to this zone |
Growing notes
- Wetland-edge plant — prefers consistently moist soil
- Long flowering season — midsummer through autumn
- Always consult a qualified medical or herbal practitioner before using any plant medicinally
Categories
Related plants
Cross-check Blue vervain against your zones