Frost Report

All states Minnesota

Frost dates for Willmar, MN

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 30

typical year

Safe to plant

May 13

frost is over in 9 of 10 years

First fall frost

October 7

typical year

Growing season

159 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 2 – 16 –
Spinach – Mar 19 – Apr 9 Aug 12 – 26
Lettuce – Apr 2 – 23 Aug 12 – 26
Radishes – Apr 2 – May 14 Aug 26 – Sep 9
Onions – Apr 2 – 16 –
Potatoes – Apr 9 – 23 –
Carrots – Apr 9 – 30 Jul 15 – 29
Beets – Apr 2 – 16 Jul 29 – Aug 12
Kale Feb 19 – Mar 5 Apr 2 – 16 Jul 29 – Aug 12
Broccoli Feb 19 – Mar 5 Apr 16 – 30 Jul 29 – Aug 12
Cabbage Feb 5 – 19 Apr 2 – 16 Jul 29 – Aug 12
Garlic – – Aug 26 – Sep 16
Warm-season crops
Tomatoes Mar 18 – Apr 1 May 13 – 27 –
Peppers Mar 11 – 25 May 20 – Jun 3 –
Cucumbers – May 13 – Jun 3 –
Zucchini – May 13 – Jun 10 –
Pumpkins – May 13 – Jun 3 –
Green beans – May 13 – Jul 29 –
Sweet corn – May 13 – Jun 10 –
Basil Apr 8 – 22 May 20 – 27 –

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 13April 30April 16
Fall frost before September 23October 7October 21

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 19 (May 2 in a late year), and the first one in fall around October 19.

Towns that use these dates

This is the nearest NOAA station with frost records for 5 towns.

Willmar, Raymond, Kandiyohi, Prinsburg, Blomkest

Where these dates come from

NOAA weather station WILLMAR WWTP, MN US (USC00219004), 1991–2020 climate normals. It's the nearest station for 7 zip codes, all within 13 miles:

56201, 56209, 56216, 56251, 56253, 56281, 56282

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