Minnesota · zones 3b–5a
When to plant spinach in Minnesota.
Sow between Mar 14 to Apr 25 in a typical year, keyed to Minnesota's median last frost around May 5. A second, fall sowing fits Jul 18 to Sep 5. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Spinach dates for a typical Minnesota season.
Direct sow
Mar 14 to Apr 25
Keyed to the ~May 5 last frost. Sow 0.5" deep, 3" apart.
Fall round
Jul 18 to Sep 5
Counted back from the ~Oct 1 first frost.
Harvest
~42 days later
~0.25 lb per plant over ~1 weeks.
Minnesota spans more than one climate: Zone 4 is the most common zone, but the state runs 3b to 5a. 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.