Brimson, MN frost dates
Last spring frostAny monthno frost-free season
Freezing nights219 / yrat or below 32°F
Hardiness zone3bZone 3b
Gardening where frost is possible all year
The weather station nearest Brimson, MN records freezing temperatures in every month often enough that NOAA cannot define a frost-free season. Gardening is still possible — it just means planning for frost at any time:
- Grow fast, cold-tolerant crops: Radishes, Lettuce, Spinach, Kale, Peas, Potatoes, Swiss Chard, Garlic.
- Plant once the soil can be worked — usually late spring to early summer at high elevation — and keep row covers ready for clear, still nights.
- Use season extension: cold frames, low tunnels, wall-of-water cloches or a greenhouse turn a few frost-free weeks into a real season.
- Frost-tender crops (tomatoes, squash, beans) need protection all season; choose the earliest varieties you can find.
How Brimson compares
- Nearby Duluth, MN, 62 km away, has a regular frost season (last frost May 14), a reminder of how much elevation and distance from the coast matter.
About these dates
Based on 1991–2020 NOAA climate normals for the Brimson 2s, MN weather station, 7 km away (elevation 1,486 ft (453 m)).
Frost dates near Brimson
- Hoyt Lakes frost any month
- Two Harbors May 12 · Oct 6
- Aurora frost any month
- Makinen May 12 · Oct 1
- Beaver Bay May 15 · Oct 1
- Knife River May 12 · Oct 6
- Melrude May 27 · Sep 20
- Biwabik frost any month
- Babbitt May 28 · Sep 14
- Gilbert May 12 · Oct 1
Frequently asked questions
When is the last frost in Brimson, MN?
Brimson, MN can freeze in any month, so there is no reliable last frost date. The nearest NOAA station averages 219 nights a year at or below 32°F.
What can I grow in Brimson, MN?
Fast, cold-tolerant crops such as radishes, lettuce, spinach, kale, peas and potatoes, ideally under row covers, cold frames or a greenhouse. Frost-tender crops like tomatoes need protection all season.