When to Plant Summer Squash in Zone 3
In USDA zone 3a, start seeds indoors around May 9, transplant or plant outdoors June 13 to August 2, and expect your first harvest around August 2. (3a shown here — see 3a and 3b dates separately below.)
Summer Squash planting calendar for USDA Zone 3a
Average last spring frost
May 30
Average first fall frost
September 10
Start seeds indoors
May 9
Transplant outdoors
Jun 13
Projected first harvest
Aug 2
Most summer squash mature in about 50 days, needing roughly 103 frost-free days in zone 3a.
Summer Squash planting calendar for USDA Zone 3b
Average last spring frost
May 20
Average first fall frost
September 15
Start seeds indoors
Apr 29
Transplant outdoors
Jun 3
Projected first harvest
Jul 23
Most summer squash mature in about 50 days, needing roughly 118 frost-free days in zone 3b.
Not sure whether you're in 3a or 3b? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
3 varieties of summer squash in the HomeSown library. Tap any for its full grow guide.
Common problems with summer squash
What to watch for, with identification and treatment for each
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