Frost Report

All states Wyoming

Frost dates for Bairoil, WY

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 21

typical year

Safe to plant

June 10

frost is over in 9 of 10 years

First fall frost

September 27

typical year

Growing season

126 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 23 – May 7 –
Spinach – Apr 9 – 30 Aug 2 – 16
Lettuce – Apr 23 – May 14 Aug 2 – 16
Radishes – Apr 23 – Jun 4 Aug 16 – 30
Onions – Apr 23 – May 7 –
Potatoes – Apr 30 – May 14 –
Carrots – Apr 30 – May 21 Jul 5 – 19
Beets – Apr 23 – May 7 Jul 19 – Aug 2
Kale Mar 12 – 26 Apr 23 – May 7 Jul 19 – Aug 2
Broccoli Mar 12 – 26 May 7 – 21 Jul 19 – Aug 2
Cabbage Feb 26 – Mar 12 Apr 23 – May 7 Jul 19 – Aug 2
Garlic – – Aug 16 – Sep 6
Warm-season crops
Tomatoes Apr 15 – 29 Jun 10 – 24 –
Peppers Apr 8 – 22 Jun 17 – Jul 1 –
Cucumbers – Jun 10 – Jul 1 –
Zucchini – Jun 10 – Jul 8 –
Pumpkins – Jun 10 – Jul 1 –
Green beans – Jun 10 – Jul 19 –
Sweet corn – Jun 10 – Jul 8 –
Basil May 6 – 20 Jun 17 – 24 –

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 10May 21May 6
Fall frost before September 12September 27October 9

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 6 (May 28 in a late year), and the first one in fall around October 5.

Towns that use these dates

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

Bairoil

Where these dates come from

NOAA weather station MUDDY GAP, WY US (USC00486595), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 10 miles:

82322

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