When to Plant Broccoli in Zone 4
In USDA zone 4a, start seeds indoors around March 13, transplant or plant outdoors April 24 to June 28, and expect your first harvest around June 28. Zone 4 also has a fall planting window opening around July 5. (4a shown here — see 4a and 4b dates separately below.)
Broccoli planting calendar for USDA Zone 4a
Average last spring frost
May 15
Average first fall frost
September 20
spring planting
Start seeds indoors
Mar 13
Transplant outdoors
Apr 24
Projected first harvest
Jun 28
fall planting
Start seeds indoors
May 31
Transplant outdoors
Jul 5
Projected first harvest
Sep 8
spring planting
fall planting
Most broccoli mature in about 50 to 200 days depending on the variety, needing roughly 128 frost-free days in zone 4a.
Broccoli planting calendar for USDA Zone 4b
Average last spring frost
May 10
Average first fall frost
September 25
spring planting
Start seeds indoors
Mar 8
Transplant outdoors
Apr 19
Projected first harvest
Jun 23
fall planting
Start seeds indoors
Jun 5
Transplant outdoors
Jul 10
Projected first harvest
Sep 13
spring planting
fall planting
Most broccoli mature in about 50 to 200 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
4 varieties of broccoli in the HomeSown library. Tap any for its full grow guide.
Common problems with broccoli
What to watch for, with identification and treatment for each
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