Herb · Lamiaceae
When to plant basil
The most cold-sensitive common herb. It blackens at temperatures that leave tomatoes untouched.
Start seed indoors
4 weeks before
Counted from your last spring frost.
Plant out
2 weeks after
Counted from your last spring frost.
Sow direct
2 weeks after
Counted from your last spring frost.
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 basil plantable anywhere.
- Start seed indoors 4 weeks before the last frost.
- Plant out 2 weeks after the last frost.
- Sow direct 2 weeks after the last frost.
- Expect 50–70 days to maturity, counted from sowing.
- Sow again every 21 days for a continuous supply.
Getting the timing right
Plant out two weeks after last frost, once nights are reliably above 12C. A second sowing in midsummer replaces plants that have gone to flower.
Frost tolerance
Damaged at 1C, before any actual frost forms. If your forecast shows 2C, basil should already be indoors.
Classified as tender, with damage expected below 1°C (33.8°F)33.8°F (1°C).