USDA Zone 2 planting calendar
When to plant kale in USDA zone 2
Sowing, transplant, and harvest dates calibrated to zone 2's 90-day season (Northern Alaska, parts of northern Canada).
Key dates for kale in zone 2
| Stage | When | Anchor |
|---|---|---|
| Indoor seed start | late April (April 24) | 6 weeks before last frost |
| Outdoor transplant | early May (May 8) | 28 days before last frost (early June) |
| First harvest (estimate) | early July (July 7) | ~60 days from transplant |
Dates are zone-wide averages. Local microclimates (south-facing slopes, urban heat, lakeside warmth, elevation) can shift the planting window by 1-2 weeks within the same zone.
Why this timing works for zone 2
Zone 2 has average annual minimum temperatures of -50 to -40°F and a 90-day frost-free window from early June to late August. Kale are hardy enough to handle light frost — and in fact prefer cool weather. They bolt or turn bitter once daytime temperatures consistently climb above 24 °C, which is why earlier is better in zone 2.
Kale is among the hardiest brassicas, surviving temperatures as low as −12 °C (10 °F) in protected conditions; frost sweetens the leaves by converting starches to sugars. Transplant or direct-sow 4–6 weeks before last spring frost; can also be direct-sown. For fall/winter harvest, direct-sow or transplant 6–8 weeks before first autumn frost. Avoid planting when temperatures consistently exceed 27 °C (80 °F) as heat reduces palatability and increases bitterness. Harvest outer leaves continuously to extend production; the plant does not form a head and can be harvested over many months.
Quick-grow guide
- Sun: Full sun to part shade — 4–6+ hours direct.
- Soil temperature for germination: 7–29 °C (45–85 °F).
- Spacing: 12–18 inches (30–45 cm) between plants.
- Days to harvest from transplant: ~60 days.
- Plant in cool weather and provide afternoon shade once temperatures climb above 24 °C.
Common mistakes — zone 2 × kale
- Planting before last frost: zone 2's last frost averages early June, and even a light frost will kill kale seedlings overnight.
- Skipping hardening off: even healthy indoor transplants need 7-10 days of progressive outdoor exposure before going in the ground.
Source and methodology
Frost-date averages from NOAA Climate Data Online within each USDA hardiness zone. Hardiness zone boundaries from the USDA Plant Hardiness Zone Map (2023). Crop timing offsets calibrated against US Cooperative Extension Service publications (UNL, UMN, NC State, Texas A&M, UF/IFAS) and cross-checked against the RHS sowing calendar for en-GB readers. Curated by the Growli editorial team.
Keep going
- How to grow kale — full guide
- USDA Zone 2 — frost dates and what else to plant
- All 13 USDA hardiness zones