Frost Report

All states Illinois

Frost dates for Rockford, IL

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 8

frost is over in 9 of 10 years

First fall frost

October 17

typical year

Growing season

174 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 22 – Sep 5
Lettuce – Mar 27 – Apr 17 Aug 22 – Sep 5
Radishes – Mar 27 – May 8 Sep 5 – 19
Onions – Mar 27 – Apr 10 –
Potatoes – Apr 3 – 17 –
Carrots – Apr 3 – 24 Jul 25 – Aug 8
Beets – Mar 27 – Apr 10 Aug 8 – 22
Kale Feb 13 – 27 Mar 27 – Apr 10 Aug 8 – 22
Broccoli Feb 13 – 27 Apr 10 – 24 Aug 8 – 22
Cabbage Jan 30 – Feb 13 Mar 27 – Apr 10 Aug 8 – 22
Garlic – – Sep 5 – 26
Warm-season crops
Tomatoes Mar 13 – 27 May 8 – 22 –
Peppers Mar 6 – 20 May 15 – 29 –
Cucumbers – May 8 – 29 –
Zucchini – May 8 – Jun 5 –
Pumpkins – May 8 – 29 –
Green beans – May 8 – Aug 8 –
Sweet corn – May 8 – Jun 5 –
Basil Apr 3 – 17 May 15 – 22 –

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 8April 24April 10
Fall frost before October 2October 17October 30

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 13 (April 27 in a late year), and the first one in fall around October 28.

Towns that use these dates

This is the nearest NOAA station with frost records for 10 towns.

Rockford, Belvidere, Loves Park, Byron, Winnebago, Cherry Valley, Davis Junction, Stillman Valley, New Milford, Monroe Center

Where these dates come from

NOAA weather station ROCKFORD GTR ROCKFORD AP, IL US (USW00094822), 1991–2020 climate normals. It's the nearest station for 18 zip codes, all within 13 miles:

61010, 61016, 61020, 61043, 61052, 61077, 61084, 61088, 61101, 61102, 61103, 61104, 61107, 61108, 61109, 61111, 61112, 61114

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