Polaris, MT frost dates

Gardening where frost is possible all year

The weather station nearest Polaris, MT 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.

About these dates

Based on 1991–2020 NOAA climate normals for the Jackson, MT weather station, 23 km away (elevation 6,480 ft (1,975 m)).

Frost dates near Polaris

• Jackson frost any month
• Glen frost any month
• Dillon Jun 5 · Sep 13
• Wisdom frost any month
• Wise River frost any month
• Melrose frost any month
• Divide Jun 10 · Sep 7
• Twin Bridges Jun 8 · Sep 2
• Sheridan May 24 · Sep 22
• Butte Jun 13 · Sep 5

Frequently asked questions

When is the last frost in Polaris, MT?

Polaris, MT can freeze in any month, so there is no reliable last frost date. The nearest NOAA station averages 250 nights a year at or below 32°F.

What can I grow in Polaris, MT?

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.