When to Plant Onions in Zone 9
In USDA zone 9a, plant outdoors December 7 to March 27, and expect your first harvest around March 27. (9a shown here — see 9a and 9b dates separately below.)
Onions planting calendar for USDA Zone 9a
Average last spring frost
March 1
Average first fall frost
December 1
Direct sow
Dec 7
Projected first harvest
Mar 27
Most onions mature in about 90 to 110 days depending on the variety, needing roughly 275 frost-free days in zone 9a.
Onions planting calendar for USDA Zone 9b
Average last spring frost
February 15
Average first fall frost
December 15
Direct sow
Nov 23
Projected first harvest
Mar 13
Most onions mature in about 90 to 110 days depending on the variety, needing roughly 303 frost-free days in zone 9b.
Not sure whether you're in 9a or 9b? 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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