What Can Grow in Duluth, MN

Duluth on Lake Superior has one of the coldest climates in the lower 48 — but summer lake effect moderates heat.

Duluth, MN is in USDA Hardiness Zone 3b. The growing season lasts about 100 days, with last frost around May 25 and first fall frost around August 30. Top crops include kale, potatoes, root vegetables.

3bUSDA Zone
100 daysFrost-Free
May 25Last Frost
August 30First Frost
🌱 What Grows in Duluth
kalepotatoesroot vegetablesbrassicaspeasbeets
💡 Planting Tips

Very short season. Cold-hardy only. Use cold frames. Lake Superior moderates some temperatures.

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🔗 More Resources
📍 Full Zone 3b Guide 🌎 Minnesota Planting Guide

Frequently Asked Questions

Duluth, MN is in USDA Plant Hardiness Zone 3b. Duluth on Lake Superior has one of the coldest climates in the lower 48 — but summer lake effect moderates heat.

The average last spring frost in Duluth is around May 25. The first fall frost typically arrives around August 30, giving a frost-free growing season of approximately 100 days.

Duluth's Zone 3b climate supports growing kale, potatoes, root vegetables, brassicas, peas, beets. Very short season. Cold-hardy only. Use cold frames. Lake Superior moderates some temperatures.

In Duluth, start with cool-season crops like lettuce, spinach, and broccoli a few weeks before the last frost date of May 25. Warm-season crops like tomatoes and peppers should go in after all frost risk has passed.