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Plant Broccoli in Zone 4b

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

Start indoors
Mar 24
Transplant
Apr 21
Harvest (~65d)
Jun 25

In Zone 4b, 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 5
First fall frost
Sep 28
Growing season
146 days

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

Frequently asked questions

When should I start broccoli in Zone 4b?

Start broccoli seeds indoors around Mar 24 (Zone 4b).

Can I direct sow broccoli in Zone 4b?

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