Frost Report

All states Montana

Frost dates for Dodson, MT

When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.

Last spring frost

May 24

typical year

Safe to plant

June 11

frost is over in 9 of 10 years

First fall frost

September 22

typical year

Growing season

118 days

frost-free, typical year

When to plant

Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.

CropStart indoorsPlant outsideFall planting
Cool-season crops
Peas – Apr 26 – May 10 –
Spinach – Apr 12 – May 3 Jul 28 – Aug 11
Lettuce – Apr 26 – May 17 Jul 28 – Aug 11
Radishes – Apr 26 – Jun 7 Aug 11 – 25
Onions – Apr 26 – May 10 –
Potatoes – May 3 – 17 –
Carrots – May 3 – 24 Jun 30 – Jul 14
Beets – Apr 26 – May 10 Jul 14 – 28
Kale Mar 15 – 29 Apr 26 – May 10 Jul 14 – 28
Broccoli Mar 15 – 29 May 10 – 24 Jul 14 – 28
Cabbage Mar 1 – 15 Apr 26 – May 10 Jul 14 – 28
Garlic – – Aug 11 – Sep 1
Warm-season crops
Tomatoes Apr 16 – 30 Jun 11 – 25 –
Peppers Apr 9 – 23 Jun 18 – Jul 2 –
Cucumbers – Jun 11 – Jul 2 –
Zucchini – Jun 11 – Jul 9 –
Pumpkins – Jun 11 – Jul 2 –
Green beans – Jun 11 – Jul 14 –
Sweet corn – Jun 11 – Jul 9 –
Basil May 7 – 21 Jun 18 – 25 –

Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.

The year at a glance

Start indoors Plant outside Fall planting

The chance of frost, by date

1 year in 10Half of years9 years in 10
Spring frost after June 11May 24May 12
Fall frost before September 8September 22October 3

Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.

Hard freeze (28°F)

A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around May 12 (May 25 in a late year), and the first one in fall around October 1.

Towns that use these dates

This is the nearest NOAA station with frost records for 1 town.

Dodson

Where these dates come from

NOAA weather station HARLEM 20S, MT US (USC00243934), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 14 miles:

59524

Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.