Frost Report

All states Washington

Frost dates for Morton, 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

April 24

typical year

Safe to plant

May 12

frost is over in 9 of 10 years

First fall frost

October 15

typical year

Growing season

176 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 – Mar 27 – Apr 10 –
Spinach – Mar 13 – Apr 3 Aug 20 – Sep 3
Lettuce – Mar 27 – Apr 17 Aug 20 – Sep 3
Radishes – Mar 27 – May 8 Sep 3 – 17
Onions – Mar 27 – Apr 10 –
Potatoes – Apr 3 – 17 –
Carrots – Apr 3 – 24 Jul 23 – Aug 6
Beets – Mar 27 – Apr 10 Aug 6 – 20
Kale Feb 13 – 27 Mar 27 – Apr 10 Aug 6 – 20
Broccoli Feb 13 – 27 Apr 10 – 24 Aug 6 – 20
Cabbage Jan 30 – Feb 13 Mar 27 – Apr 10 Aug 6 – 20
Garlic – – Sep 3 – 24
Warm-season crops
Tomatoes Mar 17 – 31 May 12 – 26 –
Peppers Mar 10 – 24 May 19 – Jun 2 –
Cucumbers – May 12 – Jun 2 –
Zucchini – May 12 – Jun 9 –
Pumpkins – May 12 – Jun 2 –
Green beans – May 12 – Aug 6 –
Sweet corn – May 12 – Jun 9 –
Basil Apr 7 – 21 May 19 – 26 –

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 12April 24March 31
Fall frost before September 24October 15November 8

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 March 26 (April 18 in a late year), and the first one in fall around November 5.

Towns that use these dates

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

Morton

Where these dates come from

NOAA weather station GLENOMA, WA US (USC00453177), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 8 miles:

98336, 98356

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