Frost Report

All states Minnesota

Frost dates for Thorhult, 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

May 24

typical year

Safe to plant

June 7

frost is over in 9 of 10 years

First fall frost

September 20

typical year

Growing season

120 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 26 – May 10 –
Spinach – Apr 12 – May 3 Jul 26 – Aug 9
Lettuce – Apr 26 – May 17 Jul 26 – Aug 9
Radishes – Apr 26 – Jun 7 Aug 9 – 23
Onions – Apr 26 – May 10 –
Potatoes – May 3 – 17 –
Carrots – May 3 – 24 Jun 28 – Jul 12
Beets – Apr 26 – May 10 Jul 12 – 26
Kale Mar 15 – 29 Apr 26 – May 10 Jul 12 – 26
Broccoli Mar 15 – 29 May 10 – 24 Jul 12 – 26
Cabbage Mar 1 – 15 Apr 26 – May 10 Jul 12 – 26
Garlic – – Aug 9 – 30
Warm-season crops
Tomatoes Apr 12 – 26 Jun 7 – 21 –
Peppers Apr 5 – 19 Jun 14 – 28 –
Cucumbers – Jun 7 – 28 –
Zucchini – Jun 7 – Jul 5 –
Pumpkins – Jun 7 – 28 –
Green beans – Jun 7 – Jul 12 –
Sweet corn – Jun 7 – Jul 5 –
Basil May 3 – 17 Jun 14 – 21 –

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 7May 24May 7
Fall frost before September 4September 20October 3

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 12 (May 29 in a late year), and the first one in fall around October 1.

Where these dates come from

NOAA weather station THORHULT, MN US (USC00218254), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 11 miles:

56727

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