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Plant Onions in Zone 5a

Seed-starting, transplant & harvest dates for USDA Zone 5a

Start indoors
Feb 19
Transplant
Apr 16
Harvest (~100d)
Jul 25

In Zone 5a, the average last spring frost is around April. Onions is a hardy crop, so give it a head start indoors about 10 weeks before that, then move it out after frost danger passes.

Last spring frost
Apr 30
First fall frost
Oct 3
Growing season
156 days

Full Onions grow guide → · All crops for Zone 5a →

Frequently asked questions

When should I start onions in Zone 5a?

Start onions seeds indoors around Feb 19 (Zone 5a).

Can I direct sow onions in Zone 5a?

Onions is best started indoors and transplanted in Zone 5a rather than direct sown.