Sweetcorn · Edmonton, Alberta, Canada

When to plant sweetcorn in Edmonton

Main outdoor window

20 May - 3 Jun

The window this page is built around.

Timed from last spring frost

13 May

In Edmonton, on your chosen risk.

Ready to pick

19 Jul - 28 Aug

If you plant at the start of the window.

The average last frost. Half of all years are later than this.

Cautious Balanced Bold

Step by step in Edmonton

Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.

Sow direct

20 May - 3 Jun

One week after your last frost.

Harvest

19 Jul - 28 Aug

Sow in succession. A single sowing gives you a single glut. Sow a short row every 14 days through the window above and you get a steady supply instead.

Frost tolerance

Tender

Damaged below

0°C (32°F)

Days to maturity

60–100

Min soil temp

15°C (59°F)

Spacing

30 cm

Sowing depth

30 mm (1.2 in)

Sun

Full

Sweetcorn through the year

Against the frost risk in Edmonton

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Sweetcorn

Frost risk Sow direct Harvest Today

Why these dates

Seed rots in cold wet soil. Sowing a week after last frost into 15C soil beats sowing on the frost date into 10C soil almost every time.

Seedlings survive a very light frost if the growing point is still below soil level, but growth stalls. Mature plants are killed outright.

Seed packets and extension guides express timing as weeks either side of the last spring frost, because that is the only reference point that travels. Sweetcorn are timed for direct sowing 1 weeks after it, and this page simply resolves those offsets against the frost date computed for Edmonton.

The median frost-free season here is 137 days, against 60 to 100 days to maturity for this crop counted from sowing. That margin is what decides whether a late sowing is worth attempting.

See every crop timed for Edmonton →

Also in Edmonton

Other vegetables to time

Tomatoes tender Lettuce half hardy Potatoes half hardy Courgettes tender Sweet peppers tender Carrots hardy Cucumbers tender Green beans tender Peas hardy Garlic very hardy Chilli peppers tender

Growing sweetcorn in Edmonton

When should I plant sweetcorn in Edmonton?

Aim for 20 May - 3 Jun in an average year. If you would rather not gamble on the weather, wait until 29 May - 12 Jun - by then frost has finished in nine years out of ten.

When will sweetcorn be ready to harvest in Edmonton?

Expect to start picking around 19 Jul - 28 Aug, based on 60 to 100 days to maturity from the planting date calculated for this location.

How much frost will sweetcorn tolerate?

Seedlings survive a very light frost if the growing point is still below soil level, but growth stalls. Mature plants are killed outright.