Frost Report

All states Idaho

Frost dates for Garden City, 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 17

typical year

Safe to plant

June 10

frost is over in 9 of 10 years

First fall frost

October 12

typical year

Growing season

147 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 19 – May 3 –
Spinach – Apr 5 – 26 Aug 17 – 31
Lettuce – Apr 19 – May 10 Aug 17 – 31
Radishes – Apr 19 – May 31 Aug 31 – Sep 14
Onions – Apr 19 – May 3 –
Potatoes – Apr 26 – May 10 –
Carrots – Apr 26 – May 17 Jul 20 – Aug 3
Beets – Apr 19 – May 3 Aug 3 – 17
Kale Mar 8 – 22 Apr 19 – May 3 Aug 3 – 17
Broccoli Mar 8 – 22 May 3 – 17 Aug 3 – 17
Cabbage Feb 22 – Mar 8 Apr 19 – May 3 Aug 3 – 17
Garlic – – Aug 31 – Sep 21
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 – Aug 3 –
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 17April 27
Fall frost before September 27October 12October 30

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 27 (May 19 in a late year), and the first one in fall around October 24.

Towns that use these dates

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

Garden City, Horseshoe Bend

Where these dates come from

NOAA weather station BOISE 7 N, ID US (USC00101017), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 13 miles:

83629, 83702, 83703, 83714

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