Michigan · zones 4b–6b
When to plant tomatoes in Michigan.
Sow or transplant between May 12 to Jul 12 in a typical year, keyed to Michigan's median last frost around May 5. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Tomatoes dates for a typical Michigan season.
1 · Start indoors
Mar 31 to May 31
About 6 weeks before set-out. Warm spot, real light.
2 · Set out
May 12 to Jul 12
Keyed to the ~May 5 last frost. Sow 0.25" deep, 24" apart.
Harvest
~73 days later
~12 lb per plant over ~8 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.