When should I plant Thai Basil in Zone 4a?

Start Thai Basil seeds indoors around 24 Th3. Transplant outdoors after 19 Th5. Expect first harvest around 18 Th6.

What is the last frost date for Zone 4a?

The average last spring frost date for Zone 4a is 5 Th5. The first fall frost averages 1 Th10, giving a 149-day growing season.

Can I grow Thai Basil in Zone 4a?

Yes. Thai Basil needs 40 days to harvest. Zone 4a has a 149-day growing season, which is sufficient. You can plant up to 5 successions.

Growing Thai Basil in Zone 4a

Zone 4a has cold winters and a moderate growing season. Timing is key for Thai Basil in this zone. Sương giá cuối: 5 Th5. Sương giá đầu: 1 Th10.

Planting Calendar

Indoor

Outdoor

Harvest

24 Th31 Th10

Season: 5 Th5 – 1 Th10 (149 ngày) · Succession: plant every 3 weeks (up to 5x)

Vùng4a

Sương giá cuối5 Th5

Sương giá đầu1 Th10

Mùa vụ149 ngày

Thu hoạch40 ngày

Ánh sángNắng hoàn toàn

When to Plant Thai Basil in Zone 4a

Start Seeds Indoors: 24 Th3

Start Thai Basil seeds indoors around 24 Th3 (6 tuần trước sương giá cuối). Optimal germination temperature: 80F. Germinates in 5-10 days.

Transplant Outdoors: 19 Th5

Transplant Thai Basil seedlings outdoors after 19 Th5. Wait until soil temperature reaches 60F. Space plants at 4/m² (15cm khoảng cách). Harden off plants for a week before moving outside.

Harvest: 18 Th6

First harvest approximately 18 Th6 (~30 ngày from transplant). Continue harvesting until first frost (1 Th10).

Thai Basil in Other Zones

1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13b

Plan Your Garden Thai Basil

Track Thai Basil from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

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