Frost Report

All states Montana

Frost dates for Terry, 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 26

typical year

Safe to plant

June 13

frost is over in 9 of 10 years

First fall frost

September 17

typical year

Growing season

113 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 28 – May 12 –
Spinach – Apr 14 – May 5 Jul 23 – Aug 6
Lettuce – Apr 28 – May 19 Jul 23 – Aug 6
Radishes – Apr 28 – Jun 9 Aug 6 – 20
Onions – Apr 28 – May 12 –
Potatoes – May 5 – 19 –
Carrots – May 5 – 26 Jun 25 – Jul 9
Beets – Apr 28 – May 12 Jul 9 – 23
Kale Mar 17 – 31 Apr 28 – May 12 Jul 9 – 23
Broccoli Mar 17 – 31 May 12 – 26 Jul 9 – 23
Cabbage Mar 3 – 17 Apr 28 – May 12 Jul 9 – 23
Garlic – – Aug 6 – 27
Warm-season crops
Tomatoes Apr 18 – May 2 Jun 13 – 27 –
Peppers Apr 11 – 25 Jun 20 – Jul 4 –
Cucumbers – Jun 13 – Jul 4 –
Zucchini – Jun 13 – Jul 11 –
Pumpkins Season usually too short. Try a quick variety or row covers.
Green beans – Jun 13 – Jul 9 –
Sweet corn – Jun 13 – Jul 11 –
Basil May 9 – 23 Jun 20 – 27 –

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 13May 26May 13
Fall frost before September 1September 17September 29

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 15 (May 30 in a late year), and the first one in fall around September 27.

Where these dates come from

NOAA weather station TERRY 21 NNW, MT US (USC00248169), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 15 miles:

59339

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