Frost Report

All states Illinois

Frost dates for Mount Vernon, 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 11

typical year

Safe to plant

April 26

frost is over in 9 of 10 years

First fall frost

October 22

typical year

Growing season

193 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 14 – 28 –
Spinach – Feb 28 – Mar 21 Aug 27 – Sep 10
Lettuce – Mar 14 – Apr 4 Aug 27 – Sep 10
Radishes – Mar 14 – Apr 25 Sep 10 – 24
Onions – Mar 14 – 28 –
Potatoes – Mar 21 – Apr 4 –
Carrots – Mar 21 – Apr 11 Jul 30 – Aug 13
Beets – Mar 14 – 28 Aug 13 – 27
Kale Jan 31 – Feb 14 Mar 14 – 28 Aug 13 – 27
Broccoli Jan 31 – Feb 14 Mar 28 – Apr 11 Aug 13 – 27
Cabbage Jan 17 – 31 Mar 14 – 28 Aug 13 – 27
Garlic – – Sep 10 – Oct 1
Warm-season crops
Tomatoes Mar 1 – 15 Apr 26 – May 10 –
Peppers Feb 22 – Mar 8 May 3 – 17 –
Cucumbers – Apr 26 – May 17 –
Zucchini – Apr 26 – May 24 –
Pumpkins – Apr 26 – May 17 –
Green beans – Apr 26 – Aug 13 –
Sweet corn – Apr 26 – May 24 –
Basil Mar 22 – Apr 5 May 3 – 10 –

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 26April 11March 30
Fall frost before October 9October 22November 1

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 1 (April 17 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 7 towns.

Mount Vernon, Wayne City, Woodlawn, Bluford, Bonnie, Belle Rive, Keenes

Where these dates come from

NOAA weather station MT VERNON 3 NE, IL US (USC00115943), 1991–2020 climate normals. It's the nearest station for 6 zip codes, all within 12 miles:

62810, 62814, 62851, 62864, 62872, 62889

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