Frost Report

All states Illinois

Frost dates for Ste. Marie, 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 13

typical year

Safe to plant

April 27

frost is over in 9 of 10 years

First fall frost

October 22

typical year

Growing season

191 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 16 – 30 –
Spinach – Mar 2 – 23 Aug 27 – Sep 10
Lettuce – Mar 16 – Apr 6 Aug 27 – Sep 10
Radishes – Mar 16 – Apr 27 Sep 10 – 24
Onions – Mar 16 – 30 –
Potatoes – Mar 23 – Apr 6 –
Carrots – Mar 23 – Apr 13 Jul 30 – Aug 13
Beets – Mar 16 – 30 Aug 13 – 27
Kale Feb 2 – 16 Mar 16 – 30 Aug 13 – 27
Broccoli Feb 2 – 16 Mar 30 – Apr 13 Aug 13 – 27
Cabbage Jan 19 – Feb 2 Mar 16 – 30 Aug 13 – 27
Garlic – – Sep 10 – Oct 1
Warm-season crops
Tomatoes Mar 2 – 16 Apr 27 – May 11 –
Peppers Feb 23 – Mar 9 May 4 – 18 –
Cucumbers – Apr 27 – May 18 –
Zucchini – Apr 27 – May 25 –
Pumpkins – Apr 27 – May 18 –
Green beans – Apr 27 – Aug 13 –
Sweet corn – Apr 27 – May 25 –
Basil Mar 23 – Apr 6 May 4 – 11 –

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 April 27April 13March 31
Fall frost before October 6October 22November 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 April 2 (April 16 in a late year), and the first one in fall around November 1.

Towns that use these dates

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

Ste. Marie, Willow Hill

Where these dates come from

NOAA weather station NEWTON 6 SSE, IL US (USC00116159), 1991–2020 climate normals. It's the nearest station for 5 zip codes, all within 12 miles:

62425, 62434, 62459, 62475, 62480

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