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Plant Broccoli in Zone 4a

Seed-starting, transplant & harvest dates for USDA Zone 4a

Start indoors
Mar 29
Transplant
Apr 26
Harvest (~65d)
Jun 30

In Zone 4a, the average last spring frost is around May. Broccoli is a half-hardy crop, so give it a head start indoors about 6 weeks before that, then move it out after frost danger passes.

Last spring frost
May 10
First fall frost
Sep 22
Growing season
135 days

Full Broccoli grow guide → · All crops for Zone 4a →

Frequently asked questions

When should I start broccoli in Zone 4a?

Start broccoli seeds indoors around Mar 29 (Zone 4a).

Can I direct sow broccoli in Zone 4a?

Broccoli is best started indoors and transplanted in Zone 4a rather than direct sown.