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When to Plant Onions in Zone 10

In USDA zone 10a, plant outdoors November 7 to February 25, and expect your first harvest around February 25. (10a shown here — see 10a and 10b dates separately below.)

Onions planting calendar for USDA Zone 10a

Average last spring frost

January 30

Average first fall frost

December 30

🌿

Direct sow

Nov 7

🌾

Projected first harvest

Feb 25

J
F
M
A
M
J
J
A
S
O
N
D
🌱 Start indoors🌿 Growing outside🌾 HarvestTodayZone 10a (approximate)

Most onions mature in about 90 to 110 days depending on the variety, needing roughly 334 frost-free days in zone 10a.

Onions planting calendar for USDA Zone 10b

Average last spring frost

January 30

Average first fall frost

December 30

🌿

Direct sow

Nov 7

🌾

Projected first harvest

Feb 25

J
F
M
A
M
J
J
A
S
O
N
D
🌱 Start indoors🌿 Growing outside🌾 HarvestTodayZone 10b (approximate)

Most onions mature in about 90 to 110 days depending on the variety, needing roughly 334 frost-free days in zone 10b.

Not sure whether you're in 10a or 10b? 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.

Cipollini Onion →Pearl Onion →Red Onion →Spanish Onion →Vidalia Sweet Onion →Walla Walla Sweet Onion →White Onion →Yellow Sweet Onion →

Common problems with onions

What to watch for, with identification and treatment for each

Onion MaggotLeek MothSeed Corn MaggotSeedcorn MaggotBulb MiteWirewormsPink RootBotrytis Neck RotFusarium Basal RotWhite RotCracking & SplittingBulb Rot

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When to plant onions in other zones

All zonesZone 3 →Zone 4 →Zone 5 →Zone 6 →Zone 7 →Zone 8 →Zone 9 →