Vegetable · Poaceae
When to plant sweetcorn
Wind-pollinated, so plant in a block rather than a row. Sow direct into warm soil.
Sow direct
1 week after
Counted from your last spring frost.
Days to maturity
60-100
From sowing to a first picking.
Frost tolerance
Tender
How much cold the plant itself will take.
Those weeks become real dates once you name a place.
Timing, in frost-relative terms
Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make sweetcorn plantable anywhere.
- Sow direct 1 week after the last frost.
- Expect 60–100 days to maturity, counted from sowing.
- Sow again every 14 days for a continuous supply.
Getting the timing right
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.
Frost tolerance
Seedlings survive a very light frost if the growing point is still below soil level, but growth stalls. Mature plants are killed outright.
Classified as tender, with damage expected below 0°C (32°F)32°F (0°C).