Frost Report

All states Wisconsin

Frost dates for Port Wing, 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 31

typical year

Safe to plant

June 13

frost is over in 9 of 10 years

First fall frost

October 2

typical year

Growing season

123 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 Aug 7 – 21
Lettuce – May 3 – 24 Aug 7 – 21
Radishes – May 3 – Jun 14 Aug 21 – Sep 4
Onions – May 3 – 17 –
Potatoes – May 10 – 24 –
Carrots – May 10 – 31 Jul 10 – 24
Beets – May 3 – 17 Jul 24 – Aug 7
Kale Mar 22 – Apr 5 May 3 – 17 Jul 24 – Aug 7
Broccoli Mar 22 – Apr 5 May 17 – 31 Jul 24 – Aug 7
Cabbage Mar 8 – 22 May 3 – 17 Jul 24 – Aug 7
Garlic – – Aug 21 – Sep 11
Warm-season crops
Tomatoes Apr 18 – May 2 Jun 13 – 27 –
Peppers Apr 11 – 25 Jun 20 – Jul 4 –
Cucumbers – Jun 13 – Jul 4 –
Zucchini – Jun 13 – Jul 11 –
Pumpkins – Jun 13 – Jul 4 –
Green beans – Jun 13 – Jul 24 –
Sweet corn – Jun 13 – Jul 11 –
Basil May 9 – 23 Jun 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 June 13May 31May 16
Fall frost before September 17October 2October 14

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 18 (June 1 in a late year), and the first one in fall around October 13.

Where these dates come from

NOAA weather station PORT WING, WI US (USC00476772), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 8 miles:

54844, 54865

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