Michigan · zones 4b–6b
When to plant broccoli in Michigan.
Sow or transplant between Mar 14 to Apr 11 in a typical year, keyed to Michigan's median last frost around May 5. A second, fall sowing fits Jun 24 to Aug 3. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Broccoli dates for a typical Michigan season.
1 · Start indoors
Jan 31 to Feb 28
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
Mar 14 to Apr 11
Keyed to the ~May 5 last frost. Sow 0.5" deep, 18" apart.
Fall round
Jun 24 to Aug 3
Counted back from the ~Oct 8 first frost.
Harvest
~60 days later
~1.2 lb per plant over ~3 weeks.
Michigan spans more than one climate: Zone 6 is the most common zone, but the state runs 4b to 6b. That's why the planner works from your ZIP code's frost dates, not your zone — mountain and coastal gardens in the same state can be three weeks apart.