Frost Report

All states Washington

Frost dates for Sprague, WA

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 31

typical year

Safe to plant

June 28

frost is over in 9 of 10 years

First fall frost

September 12

typical year

Growing season

101 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 3 – 17 –
Spinach – Apr 19 – May 10 Jul 18 – Aug 1
Lettuce – May 3 – 24 Jul 18 – Aug 1
Radishes – May 3 – Jun 14 Aug 1 – 15
Onions – May 3 – 17 –
Potatoes Season usually too short. Try a quick variety or row covers.
Carrots – May 10 – 31 Jun 20 – Jul 4
Beets – May 3 – 17 Jul 4 – 18
Kale Mar 22 – Apr 5 May 3 – 17 Jul 4 – 18
Broccoli Mar 22 – Apr 5 May 17 – 31 Jul 4 – 18
Cabbage Mar 8 – 22 May 3 – 17 Jul 4 – 18
Garlic – – Aug 1 – 22
Warm-season crops
Tomatoes May 3 – 17 Jun 28 – Jul 12 –
Peppers Season usually too short. Try a quick variety or row covers.
Cucumbers – Jun 28 – Jul 19 –
Zucchini – Jun 28 – Jul 26 –
Pumpkins Season usually too short. Try a quick variety or row covers.
Green beans – Jun 28 – Jul 4 –
Sweet corn Season usually too short. Try a quick variety or row covers.
Basil May 24 – Jun 7 Jul 5 – 12 –

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 28May 31May 10
Fall frost before August 23September 12October 2

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 9 (May 31 in a late year), and the first one in fall around October 1.

Towns that use these dates

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

Sprague, Harrington

Where these dates come from

NOAA weather station HARRINGTON, WA US (USC00453515), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 15 miles:

99008, 99032, 99134, 99154

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