When to plant lettuce in Minnesota
Minnesota’s average last spring frost is May 6, and the first fall frost typically arrives around September 28 — about 145 frost-free days (USDA zones 3a, 3b, 4a, 4b, 5a). Lettuce needs 30–60 days to mature, which fits comfortably within Minnesota's growing season.
When to plant lettuce in Minnesota: the short answer
For a spring planting, plant out Apr 15 – May 2, with seeds started indoors Apr 1 – Apr 15. Seeds germinate in soil from 35 to 80°F.
Succession sow again in Minnesota: May 4 · May 16 · May 28 · Jun 9
Spring succession stops before summer heat makes it bolt. Start sowing again in late summer for a fall crop (see the fall window above).
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow lettuce in Minnesota, step by step
- Start seeds indoors (Apr 1 – Apr 15). Sow seeds ⅛ inch deep in seed-starting mix under bright light. They take 2-10 days to sprout, fastest in soil around 65°F. Harden seedlings off for a week before they go outside.
- Prepare the bed. It needs six or more hours of sun for the best growth, though four to six hours in partial shade is enough and loose soil at least 8 inches deep, with a pH between 6.0 and 7.0. Dig in compost before planting.
- Plant out (Apr 15 – May 2). Space plants about 10 inches apart in rows 14 inches apart. It tolerates a light frost but not a hard freeze. As a cool-season crop it does best before summer heat arrives in Minnesota.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: aphids, slugs, snails, cutworm. Diseases and disorders: downy mildew, bottom rot, tipburn (calcium disorder).
- Harvest (from about May 22 – Jun 21). Lettuce takes 30-60 days to reach harvest. Seed needs light - barely cover it. Will not germinate above ~80 F soil. Loose-leaf types give the fastest, most forgiving cut-and-come-again harvest.
Figures come from our crop data; dates use Minnesota’s average frost dates. More in the full lettuce growing guide.
Lettuce planting dates by USDA zone in Minnesota
Minnesota spans USDA zones 3a, 3b, 4a, 4b, 5a. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the lettuce dates shift with them.
When to plant lettuce in nearby states
Questions gardeners in Minnesota ask
When is the best time to plant lettuce in Minnesota?
Plant lettuce transplants outdoors in Minnesota between April 15 and May 2. That timing is set by Minnesota's average last spring frost of May 6.
When should I start lettuce seeds indoors in Minnesota?
Start seeds indoors between April 1 and April 15, about 4 weeks before the last frost, so the seedlings are ready to plant out from April 15.
Can I plant lettuce in the fall in Minnesota?
Yes. For a fall crop, sow between July 24 and August 10, so the crop matures in cool weather before Minnesota's first frost around September 28.
When will lettuce planted in Minnesota be ready to harvest?
Planted on time, lettuce is usually ready from about May 22 to June 21, 30-60 days after planting.
When is the last frost in Minnesota?
On average around May 6, with the first fall frost around September 28 - about 145 frost-free days. Your town may differ by two weeks or more.