Frost Report

All states Montana

Frost dates for Clyde Park, 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

June 4

typical year

Safe to plant

June 23

frost is over in 9 of 10 years

First fall frost

September 6

typical year

Growing season

92 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 – May 7 – 21 –
Spinach – Apr 23 – May 14 Jul 12 – 26
Lettuce – May 7 – 28 Jul 12 – 26
Radishes – May 7 – Jun 18 Jul 26 – Aug 9
Onions – May 7 – 21 –
Potatoes Season usually too short. Try a quick variety or row covers.
Carrots – May 14 – Jun 4 Jun 14 – 28
Beets – May 7 – 21 Jun 28 – Jul 12
Kale Mar 26 – Apr 9 May 7 – 21 Jun 28 – Jul 12
Broccoli Mar 26 – Apr 9 May 21 – Jun 4 Jun 28 – Jul 12
Cabbage Mar 12 – 26 May 7 – 21 Jun 28 – Jul 12
Garlic – – Jul 26 – Aug 16
Warm-season crops
Tomatoes Apr 28 – May 12 Jun 23 – Jul 7 –
Peppers Season usually too short. Try a quick variety or row covers.
Cucumbers – Jun 23 – Jul 14 –
Zucchini – Jun 23 – Jul 21 –
Pumpkins Season usually too short. Try a quick variety or row covers.
Green beans – Jun 23 – 28 –
Sweet corn Season usually too short. Try a quick variety or row covers.
Basil May 19 – Jun 2 Jun 30 – Jul 7 –

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 23June 4May 19
Fall frost before August 28September 6September 15

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 16 (June 2 in a late year), and the first one in fall around September 13.

Towns that use these dates

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

Clyde Park

Where these dates come from

NOAA weather station WILSALL 1S, MT US (USC00241840), 1991–2020 climate normals. It's the nearest station for 3 zip codes, all within 20 miles:

59018, 59086, 59642

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