Frost Report

All states Idaho

Frost dates for Jerome, 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 2

typical year

Safe to plant

May 30

frost is over in 9 of 10 years

First fall frost

October 14

typical year

Growing season

166 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 4 – 18 –
Spinach – Mar 21 – Apr 11 Aug 19 – Sep 2
Lettuce – Apr 4 – 25 Aug 19 – Sep 2
Radishes – Apr 4 – May 16 Sep 2 – 16
Onions – Apr 4 – 18 –
Potatoes – Apr 11 – 25 –
Carrots – Apr 11 – May 2 Jul 22 – Aug 5
Beets – Apr 4 – 18 Aug 5 – 19
Kale Feb 21 – Mar 7 Apr 4 – 18 Aug 5 – 19
Broccoli Feb 21 – Mar 7 Apr 18 – May 2 Aug 5 – 19
Cabbage Feb 7 – 21 Apr 4 – 18 Aug 5 – 19
Garlic – – Sep 2 – 23
Warm-season crops
Tomatoes Apr 4 – 18 May 30 – Jun 13 –
Peppers Mar 28 – Apr 11 Jun 6 – 20 –
Cucumbers – May 30 – Jun 20 –
Zucchini – May 30 – Jun 27 –
Pumpkins – May 30 – Jun 20 –
Green beans – May 30 – Aug 5 –
Sweet corn – May 30 – Jun 27 –
Basil Apr 25 – May 9 Jun 6 – 13 –

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 May 30May 2April 15
Fall frost before September 30October 14October 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 April 14 (May 10 in a late year), and the first one in fall around October 27.

Towns that use these dates

This is the nearest NOAA station with frost records for 2 towns.

Jerome, Wendell

Where these dates come from

NOAA weather station JEROME, ID US (USC00104670), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 10 miles:

83355

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