Frost Report

All states Wisconsin

Frost dates for Norwalk, WI

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 6

typical year

Safe to plant

May 20

frost is over in 9 of 10 years

First fall frost

October 3

typical year

Growing season

150 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 8 – 22 –
Spinach – Mar 25 – Apr 15 Aug 8 – 22
Lettuce – Apr 8 – 29 Aug 8 – 22
Radishes – Apr 8 – May 20 Aug 22 – Sep 5
Onions – Apr 8 – 22 –
Potatoes – Apr 15 – 29 –
Carrots – Apr 15 – May 6 Jul 11 – 25
Beets – Apr 8 – 22 Jul 25 – Aug 8
Kale Feb 25 – Mar 11 Apr 8 – 22 Jul 25 – Aug 8
Broccoli Feb 25 – Mar 11 Apr 22 – May 6 Jul 25 – Aug 8
Cabbage Feb 11 – 25 Apr 8 – 22 Jul 25 – Aug 8
Garlic – – Aug 22 – Sep 12
Warm-season crops
Tomatoes Mar 25 – Apr 8 May 20 – Jun 3 –
Peppers Mar 18 – Apr 1 May 27 – Jun 10 –
Cucumbers – May 20 – Jun 10 –
Zucchini – May 20 – Jun 17 –
Pumpkins – May 20 – Jun 10 –
Green beans – May 20 – Jul 25 –
Sweet corn – May 20 – Jun 17 –
Basil Apr 15 – 29 May 27 – Jun 3 –

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 20May 6April 22
Fall frost before September 20October 3October 16

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 10 in a late year), and the first one in fall around October 13.

Towns that use these dates

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

Norwalk, Melvina

Where these dates come from

NOAA weather station CASHTON 3NNW, WI US (USC00471287), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 9 miles:

54648, 54653

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