Planting Thai Basil
Thai Basil is a warm season herb in the Lamiaceae family. Getting the timing right is the difference between a strong stand and a disappointing one, so the windows below are given relative to your own last spring frost and first fall frost rather than a generic calendar date. Look up your local frost dates and count back or forward from there.
Thai Basil is started indoors 4–6 weeks before your last spring frost date, giving seedlings a head start before they move outside.
Transplant young plants outdoors 1–2 weeks after your last frost, once the danger of frost has passed.
Sow Thai Basil directly into the garden 1–2 weeks after your last frost, once the soil has warmed.
Thai Basil can be grown by starting indoors, direct sowing, and transplanting. Starting indoors gives the longest, most controlled season, while direct sowing is simplest where the season is long enough.
Spacing and Planting Depth
Give Thai Basil room to mature. The figures below come from verified extension and seed-supplier data for typical varieties.
| Spacing in row | 12 inches |
|---|---|
| Row spacing | 12 inches |
| Plants per sq ft | 1 |
| Planting depth | 0.125 inches |
| Sun requirement | Full sun |
Days to Maturity
Thai Basil reaches maturity in 60–90 days from transplant.
For a continuous harvest, sow a new batch every 21 days. Use the succession planting scheduler →
Thai Basil is ready to harvest after about 75 days. Harvest before the first fall frost, which will end the plant's productive season.
Conditions and Care
As a warm-season herb, Thai Basil needs warm soil and settled weather to thrive, and is set back or killed by frost. It is frost tender, so wait until all danger of frost has passed before planting out and harvest before the first fall frost.
Thai Basil needs full sun — give it at least six hours of direct light a day for the best growth and flavor. Sow seed about 0.125 inches deep — small seed is sown shallow and barely covered, then keep the soil evenly moist until seedlings establish.
Thai Basil belongs to the Lamiaceae family; rotating where you grow members of this family each year helps limit the build-up of soil-borne pests and disease. Because it matures relatively quickly, Thai Basil rewards succession sowing: small, repeated plantings keep a steady supply coming rather than one short glut.
Companion Plants
Pairing Thai Basil with the right neighbors can improve growth and deter pests; a few combinations are best avoided.
Grows well with: Tomato, Pepper (Bell)