When to Plant Corn Salad in Canada — Sow Dates by Region
The most cold-hardy salad green there is — a fall sowing can keep producing under mulch or snow cover deep into a Canadian winter. Sow dates for both the spring and fall (better) crop.
Corn salad, better known by its French name mâche, tolerates cold that would flatten lettuce, spinach, or nearly any other leafy green. Established plants survive down to roughly -15°C, especially with a little mulch or snow cover.
That makes the fall sowing — not the spring one — the genuinely interesting reason to grow it: a real harvest in December, January, or later in most of southern Canada, from a garden that's otherwise finished for the year.
Corn salad in Canada at a glance: Sow in early spring weeks before last frost, or better, 6–8 weeks before your first fall frost for a winter harvest. Survives down to -15°C under mulch or snow cover — the most cold-hardy leafy green available, and a genuine differentiator from lettuce and spinach.
When should you plant corn salad where you garden?
Get your city's frost dates, indoor seed-starting dates, and this week's planting jobs — three free tools.
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🥦 Shop vegetable seeds at West Coast Seeds →Corn Salad Sow Dates Across Canada
| Region (City) | Zone | Spring Sow | First Fall Frost | Fall Sow (winter crop) | Overwinter Outlook |
|---|---|---|---|---|---|
| Coastal BC (Vancouver) | 8a | Late Feb–Mar | Nov 15 | Mid-late Sep | Excellent — light mulch only |
| BC Interior (Kelowna) | 6b | Late Mar–Apr | Oct 5 | Mid-late Aug | Good — mulch + snow cover |
| Southern Ontario (Toronto) | 6b | Late Mar–Apr | Oct 15 | Late Aug–early Sep | Good — mulch + snow cover |
| Eastern Ontario (Ottawa) | 5a | Early-mid Apr | Oct 5 | Mid-late Aug | Good — reliable snow cover helps |
| Quebec (Montreal) | 5b | Early-mid Apr | Oct 5 | Mid-late Aug | Good — reliable snow cover helps |
| Prairies (Calgary) | 3b | Late Apr–May | Sep 15 | Late July–early Aug | Fair — needs a cold frame |
| Prairies (Edmonton) | 4a | Late Apr–May | Sep 20 | Late July–early Aug | Fair — needs a cold frame |
| Prairies (Winnipeg) | 3a | Late Apr–May | Sep 22 | Late July–early Aug | Fair — reliable snow cover helps |
| Maritimes (Halifax) | 6a | Late Mar–Apr | Oct 15 | Late Aug–early Sep | Good — mulch + snow cover |
Common Corn Salad Problems in Canada
Bolting from a spring sowing
Corn salad bolts in real summer heat just like lettuce. Harvest the spring crop promptly and treat the fall sowing as the main event.
Winterkill in exposed, snowless spots
Corn salad is hardy but not indestructible — a bare, windswept bed with no snow or mulch in a harsh Prairie winter can still kill it. A cold frame or thick straw mulch closes the gap.
Slow, patchy germination
Seed can be slow and uneven to sprout, especially in warm late-summer soil. Keep the seedbed consistently moist and don't give up on a bed too early.
Frequently Asked Questions
When should I plant corn salad in Canada?
Early spring works, but 6–8 weeks before your first fall frost is the better sowing — it sets up a winter harvest.
Can it really survive winter outdoors?
Yes — down to about -15°C with snow cover or mulch, far hardier than lettuce or spinach.
Does it bolt in summer?
Yes, like lettuce. That's why the fall sowing, not spring, is the crop worth prioritizing.