Cool-season biennial allium grown for thick blanched stems. Tolerates hard frost in the ground — a useful winter vegetable.
Hardiness ratings
| System | Rating | Temperature range | How to read it |
|---|---|---|---|
| USDA hardiness zone | Zone 4–9 | −34.4 °C to −1.1 °C | Zones where it can be grown as an annual — not a frost-tolerance rating |
| RHS hardiness rating | H7 | down to −20 °C | Plant needs at least this level of cold tolerance |
| Canadian plant hardiness zone | Zone 4–9 | −29 °C and warmer | Zones where it can be grown as an annual — not a frost-tolerance rating |
| Australian (ANBG) zone | Zone 1–5 | −15 °C to 10 °C | Zones where it can be grown as an annual — not a frost-tolerance rating |
As a tender annual, Leek doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.
Growing notes
- Hardiest leek cultivars (Bandit, Bleu de Solaise) overwinter through deep frost
- Earth up the stems progressively as they grow to lengthen the white blanched section
Pet caution: Leek is listed as potentially harmful to cats and/or dogs. Keep pets from grazing on it, and contact a vet if you suspect your animal has eaten some.
Categories
Related plants
Cross-check Leek against your zones