Frost Report

All states Iowa

Frost dates for Sidney, 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 19

typical year

Safe to plant

May 2

frost is over in 9 of 10 years

First fall frost

October 19

typical year

Growing season

182 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 22 – Apr 5 –
Spinach – Mar 8 – 29 Aug 24 – Sep 7
Lettuce – Mar 22 – Apr 12 Aug 24 – Sep 7
Radishes – Mar 22 – May 3 Sep 7 – 21
Onions – Mar 22 – Apr 5 –
Potatoes – Mar 29 – Apr 12 –
Carrots – Mar 29 – Apr 19 Jul 27 – Aug 10
Beets – Mar 22 – Apr 5 Aug 10 – 24
Kale Feb 8 – 22 Mar 22 – Apr 5 Aug 10 – 24
Broccoli Feb 8 – 22 Apr 5 – 19 Aug 10 – 24
Cabbage Jan 25 – Feb 8 Mar 22 – Apr 5 Aug 10 – 24
Garlic – – Sep 7 – 28
Warm-season crops
Tomatoes Mar 7 – 21 May 2 – 16 –
Peppers Feb 28 – Mar 14 May 9 – 23 –
Cucumbers – May 2 – 23 –
Zucchini – May 2 – 30 –
Pumpkins – May 2 – 23 –
Green beans – May 2 – Aug 10 –
Sweet corn – May 2 – 30 –
Basil Mar 28 – Apr 11 May 9 – 16 –

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 2April 19April 5
Fall frost before October 1October 19October 31

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 9 (April 23 in a late year), and the first one in fall around October 29.

Towns that use these dates

This is the nearest NOAA station with frost records for 5 towns.

Sidney, Hamburg, Riverton, Randolph, Thurman

Where these dates come from

NOAA weather station SIDNEY 1SSE, IA US (USC00137669), 1991–2020 climate normals. It's the nearest station for 6 zip codes, all within 10 miles:

51640, 51649, 51650, 51652, 51653, 51654

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