When to Plant Bok Choy in Zone 4
In USDA zone 4a, start seeds indoors around April 17, transplant or plant outdoors May 1 to June 20, and expect your first harvest around June 20. Zone 4 also has a fall planting window opening around July 19. (4a shown here — see 4a and 4b dates separately below.)
Bok Choy planting calendar for USDA Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
spring planting
Start seeds indoors
Apr 17
Transplant outdoors
May 1
Projected first harvest
Jun 20
fall planting
Direct sow
Jul 19
Projected first harvest
Sep 7
spring planting
fall planting
Bok Choy is ready to harvest in about 50 days, needing roughly 128 frost-free days in zone 4a.
Bok Choy planting calendar for USDA Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
spring planting
Start seeds indoors
Apr 12
Transplant outdoors
Apr 26
Projected first harvest
Jun 15
fall planting
Direct sow
Jul 24
Projected first harvest
Sep 12
spring planting
fall planting
Bok Choy is ready to harvest in about 50 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 bok choy in the HomeSown library. Tap any for its full grow guide.
Common problems with bok choy
What to watch for, with identification and treatment for each
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