Frost Report

All states Iowa

Frost dates for Burlington, IA

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 18

typical year

Safe to plant

May 3

frost is over in 9 of 10 years

First fall frost

October 20

typical year

Growing season

185 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 21 – Apr 4 –
Spinach – Mar 7 – 28 Aug 25 – Sep 8
Lettuce – Mar 21 – Apr 11 Aug 25 – Sep 8
Radishes – Mar 21 – May 2 Sep 8 – 22
Onions – Mar 21 – Apr 4 –
Potatoes – Mar 28 – Apr 11 –
Carrots – Mar 28 – Apr 18 Jul 28 – Aug 11
Beets – Mar 21 – Apr 4 Aug 11 – 25
Kale Feb 7 – 21 Mar 21 – Apr 4 Aug 11 – 25
Broccoli Feb 7 – 21 Apr 4 – 18 Aug 11 – 25
Cabbage Jan 24 – Feb 7 Mar 21 – Apr 4 Aug 11 – 25
Garlic – – Sep 8 – 29
Warm-season crops
Tomatoes Mar 8 – 22 May 3 – 17 –
Peppers Mar 1 – 15 May 10 – 24 –
Cucumbers – May 3 – 24 –
Zucchini – May 3 – 31 –
Pumpkins – May 3 – 24 –
Green beans – May 3 – Aug 11 –
Sweet corn – May 3 – 31 –
Basil Mar 29 – Apr 12 May 10 – 17 –

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 3April 18April 3
Fall frost before October 6October 20November 2

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 7 (April 23 in a late year), and the first one in fall around October 31.

Towns that use these dates

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

Stronghurst, IL, Lomax, IL

Where these dates come from

NOAA weather station BURLINGTON 2S, IA US (USC00131060), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 8 miles:

61425, 61454

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