Frost Report

All states Montana

Frost dates for Poplar, 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 6

frost is over in 9 of 10 years

First fall frost

September 14

typical year

Growing season

110 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 20 – Aug 3
Lettuce – Apr 26 – May 17 Jul 20 – Aug 3
Radishes – Apr 26 – Jun 7 Aug 3 – 17
Onions – Apr 26 – May 10 –
Potatoes – May 3 – 17 –
Carrots – May 3 – 24 Jun 22 – Jul 6
Beets – Apr 26 – May 10 Jul 6 – 20
Kale Mar 15 – 29 Apr 26 – May 10 Jul 6 – 20
Broccoli Mar 15 – 29 May 10 – 24 Jul 6 – 20
Cabbage Mar 1 – 15 Apr 26 – May 10 Jul 6 – 20
Garlic – – Aug 3 – 24
Warm-season crops
Tomatoes Apr 11 – 25 Jun 6 – 20 –
Peppers Apr 4 – 18 Jun 13 – 27 –
Cucumbers – Jun 6 – 27 –
Zucchini – Jun 6 – Jul 4 –
Pumpkins – Jun 6 – 27 –
Green beans – Jun 6 – Jul 6 –
Sweet corn – Jun 6 – Jul 4 –
Basil May 2 – 16 Jun 13 – 20 –

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 6May 24May 12
Fall frost before September 1September 14September 25

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 14 (May 26 in a late year), and the first one in fall around September 22.

Towns that use these dates

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

Poplar

Where these dates come from

NOAA weather station WOLF POINT 29 ENE, MT US (USW00094060), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 13 miles:

59213, 59255

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