Growli

Overwintering guide

How to overwinter thai basil

Verdict
Bring indoors
When
Bring indoors when nights start dropping below about 10°C, ahead of the first frost.
Hardiness
Thai Basil is hardy to roughly USDA zone 10 — winter lows around -1°C. That means it will not survive frost and needs to come inside.

Winter watering

Cut watering right back — thai basil uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.

The mistake that kills thai basil in winter

Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and thai basil rots from the base.

More thai basil care

Overwintering thai basil — FAQ

Does thai basil need to come indoors for winter?

Thai Basil is hardy to roughly USDA zone 10 — winter lows around -1°C. That means it will not survive frost and needs to come inside. Thai Basil is frost-tender, so overwintering means bringing it inside and letting it rest rather than pushing it to grow. Move it indoors well before the first frost, give it the brightest spot you have (light levels indoors drop sharply in winter), and keep it away from both cold window glass and hot radiators — the swing between the two does more damage than the cold itself.

When should I move thai basil for winter?

Bring indoors when nights start dropping below about 10°C, ahead of the first frost.

How often should I water thai basil in winter?

Cut watering right back — thai basil uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.

What kills thai basil over winter?

Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and thai basil rots from the base.