Minnesota · zones 3b–5a
When to plant lettuce in Minnesota.
Sow between Mar 28 to May 12 in a typical year, keyed to Minnesota's median last frost around May 5. A second, fall sowing fits Jul 18 to Sep 16. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Lettuce dates for a typical Minnesota season.
Direct sow
Mar 28 to May 12
Keyed to the ~May 5 last frost. Sow 0.25" deep, 6" apart.
Fall round
Jul 18 to Sep 16
Counted back from the ~Oct 1 first frost.
Harvest
~45 days later
~0.4 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.
In Minnesota: watch for
The pests that find lettuce here.
The short season here, about 149 frost-free days, keeps lettuce, leaf in front of aphids only briefly. One early row cover usually carries a planting through the worst of it.
Clusters tucked into the heart of the head.
Organic fix: Rinse well; insecticidal soap on young plants.
Ragged holes and slime trails, worse after rain.
Organic fix: Iron-phosphate bait; a diatomaceous-earth ring; hand-pick at night.
Seedlings clipped off at the soil line overnight.
Organic fix: Collars around the stems; Bt or diatomaceous earth.
Pale yellow patches boxed in by the leaf veins, with white fuzz underneath.
Organic fix: Give plants room, let them dry between waterings, clear old leaves, and pick resistant varieties.
Your season math: Minnesota gives lettuce about 149 frost-free days, and it needs roughly 45 days to a first harvest. That fits about 11 re-sown rounds across the season, so you can keep it coming instead of picking once.
Planting lettuce in Minnesota: questions
When should I plant lettuce in Minnesota?+
In a typical Minnesota year, sow lettuce between Mar 28 to May 12, keyed to the state's median last frost around May 5. There's also a fall window: Jul 18 to Sep 16. Your exact dates shift with your ZIP code and microclimate.
What USDA zone is Minnesota?+
Minnesota spans zones 3b–5a, mostly zone 4. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.
How many lettuce plants do I need?+
Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.