When to Plant Cabbage in Edmonton, AB
Published: April 24, 2026 · Updated: April 27, 2026
Extremely cold-hardy brassica — survives temperatures as low as -7°C (20°F). Start indoors 6–8 weeks before last frost, transplant 2–4 weeks before last frost, and also plant for fall harvest.
Edmonton's Canadian Zone 4a (USDA 3b) continental boreal climate has cold winters and warm summers with 18+ hours of midsummer daylight that partially compensate for the short 128-day frost-free window. Long days accelerate crop development significantly versus the same varieties at lower latitudes.
Cabbage Planting Calendar for Edmonton
Start seeds indoors: April 1–8
Transplant outdoors: April 29–May 9
Harvest window: June 28 – August 7
Minimum soil temperature: 7°C (45°F)
Days to harvest: 60–100 days
Sun requirement: Full sun (6+ hours)
Fall crop planting: July 3–13 (harvest September 1)
⚠ Start cabbage indoors 6–8 weeks before last frost. Transplant 2–4 weeks before last frost. Very frost tolerant — withstands temperatures as low as 20°F. Also plant in late summer for fall harvest.
Edmonton Climate Notes
Edmonton's long summer days (18+ hours of daylight at peak) accelerate crop development 20-30% faster than the same variety at southern latitudes. The North Saskatchewan River valley provides a sheltered microclimate measurably warmer than surrounding uplands. Short-season tomato varieties ripen reliably thanks to the long daylight.
Growing Tips for Cabbage
- Space plants 18 inches apart — crowding reduces head size and promotes fungal disease.
- Side-dress with nitrogen 3–4 weeks after transplanting to support rapid leaf formation.
- Harvest when heads feel firm; leave the root ball in the ground and small secondary heads may form.
- Fall cabbage sweetens after light frost — one of the best-tasting garden crops when harvested in October.
Companion Planting in Edmonton
Pair cabbage with Onion, Dill, Celery, Beet for mutual benefit. Avoid planting near Tomato, Strawberry, Pepper, which compete with or inhibit cabbage growth.
Pests and Problems to Watch in Edmonton
The most common pest and disease pressure on cabbage in Edmonton comes from Cabbage Worm, Cabbage Looper, Aphid, Flea Beetle. Floating row covers through the first 4–6 weeks after planting block adult pests from laying eggs, and a weekly scouting routine catches infestations before they damage the crop.
Other Alberta Cities
Frequently Asked Questions
When do I plant cabbage in Edmonton?
Edmonton's last spring frost is around May 20. Start seeds indoors April 1–8. Transplant outdoors April 29–May 9.
What Canadian hardiness zone is Edmonton?
Edmonton is in Canadian Zone 4a (USDA equivalent 3b). The continental boreal climate delivers 128 frost-free days from May 20 to September 25, which shapes every planting date in the local calendar.
How long is Edmonton's growing season?
Edmonton has 128 frost-free days — from May 20 in spring to September 25 in fall. That is more than enough time to finish a full cabbage crop (60–100 days to maturity) before the first fall frost.
Can I grow cabbage in containers in Edmonton?
Yes. Container growing on balconies and decks is practical in Edmonton — choose a 5-gallon or larger dark-coloured container to warm the root zone, use a high-quality potting mix, and water daily during hot summer weather. In Canadian Zone 3–4, a sheltered south-facing location adds 2–3 weeks to the effective season.
What is the first fall frost in Edmonton?
Edmonton's average first fall frost is September 25. For a fall cabbage crop, plant around July 3–13 so plants mature before the first killing frost.