Frost Report

All states Arizona

Frost dates for Cottonwood, AZ

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

March 30

typical year

Safe to plant

April 21

frost is over in 9 of 10 years

First fall frost

November 10

typical year

Growing season

223 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 2 – 16 –
Spinach – Feb 16 – Mar 9 Sep 15 – 29
Lettuce – Mar 2 – 23 Sep 15 – 29
Radishes – Mar 2 – Apr 13 Sep 29 – Oct 13
Onions – Mar 2 – 16 –
Potatoes – Mar 9 – 23 –
Carrots – Mar 9 – 30 Aug 18 – Sep 1
Beets – Mar 2 – 16 Sep 1 – 15
Kale Jan 19 – Feb 2 Mar 2 – 16 Sep 1 – 15
Broccoli Jan 19 – Feb 2 Mar 16 – 30 Sep 1 – 15
Cabbage Jan 5 – 19 Mar 2 – 16 Sep 1 – 15
Garlic – – Sep 29 – Oct 20
Warm-season crops
Tomatoes Feb 24 – Mar 10 Apr 21 – May 5 –
Peppers Feb 17 – Mar 3 Apr 28 – May 12 –
Cucumbers – Apr 21 – May 12 –
Zucchini – Apr 21 – May 19 –
Pumpkins – Apr 21 – May 12 –
Green beans – Apr 21 – Sep 1 –
Sweet corn – Apr 21 – May 19 –
Basil Mar 17 – 31 Apr 28 – May 5 –

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 21March 30March 9
Fall frost before October 25November 10November 23

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 March 5 (March 31 in a late year), and the first one in fall around November 20.

Towns that use these dates

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

Cottonwood, Clarkdale

Where these dates come from

NOAA weather station TUZIGOOT, AZ US (USC00028904), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 8 miles:

86325, 86326

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