Old cottage-garden biennial with dense flat heads of small fringed flowers in white, pink, red, or bicolours, with a sweet clove fragrance. Flowers in its second year at midsummer.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 3–9 | −40 °C to −1.1 °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 2–6 | −10 °C to 15 °C | Plant tolerates down to this zone |
Growing notes
- Strictly biennial in habit — sown one summer, flowers the following midsummer at the solstice, then dies
- Sow successively each summer for continuous flowering year on year
- Excellent cut flower with long vase life
- Self-seeds where happy, perpetuating itself once established
Categories
Related plants
Cross-check Sweet William against your zones