Minimum Temperatures for Basil Plants

Cold Damage

• Basil leaves are damaged by temperatures below 45 degrees Fahrenheit. The plant's stems become damaged with frost -- below 33 degrees -- and its roots will die off with the first hard freeze.

Planting Time

• Sow basil seeds after all danger of frost has passed -- about 2 weeks after the last frost. If there is a late frost advisory after sowing, cover the seeds and sprouts with a little straw or a flannel sheet.

Extending the Harvest

• Get an early start by planting greenhouse-grown plants 4 weeks after the last frost. Extend the season in fall by covering basil plants with a flannel sheet when there is an early frost advisory.