When to Plant Onions in Zone 8
In USDA zone 8a, start seeds indoors around January 21, transplant or plant outdoors March 4 to June 22, and expect your first harvest around June 22. (8a shown here — see 8a and 8b dates separately below.)
Onions planting calendar for USDA Zone 8a
Average last spring frost
April 1
Average first fall frost
November 10
Start seeds indoors
Jan 21
Transplant outdoors
Mar 4
Projected first harvest
Jun 22
Most onions mature in about 90 to 110 days depending on the variety, needing roughly 223 frost-free days in zone 8a.
Onions planting calendar for USDA Zone 8b
Average last spring frost
March 20
Average first fall frost
November 20
Start seeds indoors
Jan 9
Transplant outdoors
Feb 20
Projected first harvest
Jun 10
Most onions mature in about 90 to 110 days depending on the variety, needing roughly 245 frost-free days in zone 8b.
Not sure whether you're in 8a or 8b? Set your ZIP in HomeSown for dates tuned to your exact location.
Varieties to grow
8 varieties of onions in the HomeSown library. Tap any for its full grow guide.
Common problems with onions
What to watch for, with identification and treatment for each
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