When to Plant Spinach in Zone 4
In USDA zone 4a, start seeds indoors around March 13, transplant or plant outdoors April 17 to May 29, and expect your first harvest around May 29. Zone 4 also has a fall planting window opening around August 16. (4a shown here — see 4a and 4b dates separately below.)
Spinach 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 17
Projected first harvest
May 29
fall planting
Direct sow
Aug 16
Projected first harvest
Sep 27
spring planting
fall planting
Most spinach mature in about 41 to 45 days depending on the variety, needing roughly 128 frost-free days in zone 4a.
Spinach 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 12
Projected first harvest
May 24
fall planting
Direct sow
Aug 21
Projected first harvest
Oct 2
spring planting
fall planting
Most spinach mature in about 41 to 45 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
3 varieties of spinach in the HomeSown library. Tap any for its full grow guide.
Common problems with spinach
What to watch for, with identification and treatment for each
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