Frost Report

All states Idaho

Frost dates for Hailey, ID

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 13

typical year

Safe to plant

June 3

frost is over in 9 of 10 years

First fall frost

October 2

typical year

Growing season

139 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 15 – 29 –
Spinach – Apr 1 – 22 Aug 7 – 21
Lettuce – Apr 15 – May 6 Aug 7 – 21
Radishes – Apr 15 – May 27 Aug 21 – Sep 4
Onions – Apr 15 – 29 –
Potatoes – Apr 22 – May 6 –
Carrots – Apr 22 – May 13 Jul 10 – 24
Beets – Apr 15 – 29 Jul 24 – Aug 7
Kale Mar 4 – 18 Apr 15 – 29 Jul 24 – Aug 7
Broccoli Mar 4 – 18 Apr 29 – May 13 Jul 24 – Aug 7
Cabbage Feb 18 – Mar 4 Apr 15 – 29 Jul 24 – Aug 7
Garlic – – Aug 21 – Sep 11
Warm-season crops
Tomatoes Apr 8 – 22 Jun 3 – 17 –
Peppers Apr 1 – 15 Jun 10 – 24 –
Cucumbers – Jun 3 – 24 –
Zucchini – Jun 3 – Jul 1 –
Pumpkins – Jun 3 – 24 –
Green beans – Jun 3 – Jul 24 –
Sweet corn – Jun 3 – Jul 1 –
Basil Apr 29 – May 13 Jun 10 – 17 –

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 3May 13April 30
Fall frost before September 15October 2October 17

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 April 28 (May 11 in a late year), and the first one in fall around October 14.

Towns that use these dates

This is the nearest NOAA station with frost records for 4 towns.

Hailey, Ketchum, Bellevue, Sun Valley

Where these dates come from

NOAA weather station BELLEVUE, ID US (USC00100774), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 25 miles:

83333, 83340, 83353, 83354

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