When to Plant Basil in Zone 4
In USDA zone 4a, start seeds indoors around April 3, transplant or plant outdoors May 29 to August 2, and expect your first harvest around August 2. (4a shown here — see 4a and 4b dates separately below.)
Basil planting calendar for USDA Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
Start seeds indoors
Apr 3
Transplant outdoors
May 29
Projected first harvest
Aug 2
Most basil mature in about 60 to 75 days depending on the variety, needing roughly 128 frost-free days in zone 4a.
Basil planting calendar for USDA Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
Start seeds indoors
Mar 29
Transplant outdoors
May 24
Projected first harvest
Jul 28
Most basil mature in about 60 to 75 days depending on the variety, needing roughly 138 frost-free days in zone 4b.
Not sure whether you're in 4a or 4b? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
7 varieties of basil in the HomeSown library. Tap any for its full grow guide.
Common problems with basil
What to watch for, with identification and treatment for each
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