When to Plant Kabocha Squash in Zone 4
In USDA zone 4a, start seeds indoors around April 24, transplant or plant outdoors May 29 to September 1, and expect your first harvest around September 1. (4a shown here — see 4a and 4b dates separately below.)
Kabocha Squash planting calendar for USDA Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
Start seeds indoors
Apr 24
Transplant outdoors
May 29
Projected first harvest
Sep 1
Kabocha Squash is ready to harvest in about 95 days, needing roughly 128 frost-free days in zone 4a.
Kabocha Squash planting calendar for USDA Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
Start seeds indoors
Apr 19
Transplant outdoors
May 24
Projected first harvest
Aug 27
Kabocha Squash is ready to harvest in about 95 days, 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
1 variety of kabocha squash in the HomeSown library. Tap any for its full grow guide.
Common problems with kabocha squash
What to watch for, with identification and treatment for each
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