Frost Report

All states Arizona

Frost dates for Heber (Black Mesa) Rs, 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

May 23

typical year

Safe to plant

June 6

frost is over in 9 of 10 years

First fall frost

October 5

typical year

Growing season

135 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 – Apr 25 – May 9 –
Spinach – Apr 11 – May 2 Aug 10 – 24
Lettuce – Apr 25 – May 16 Aug 10 – 24
Radishes – Apr 25 – Jun 6 Aug 24 – Sep 7
Onions – Apr 25 – May 9 –
Potatoes – May 2 – 16 –
Carrots – May 2 – 23 Jul 13 – 27
Beets – Apr 25 – May 9 Jul 27 – Aug 10
Kale Mar 14 – 28 Apr 25 – May 9 Jul 27 – Aug 10
Broccoli Mar 14 – 28 May 9 – 23 Jul 27 – Aug 10
Cabbage Feb 28 – Mar 14 Apr 25 – May 9 Jul 27 – Aug 10
Garlic – – Aug 24 – Sep 14
Warm-season crops
Tomatoes Apr 11 – 25 Jun 6 – 20 –
Peppers Apr 4 – 18 Jun 13 – 27 –
Cucumbers – Jun 6 – 27 –
Zucchini – Jun 6 – Jul 4 –
Pumpkins – Jun 6 – 27 –
Green beans – Jun 6 – Jul 27 –
Sweet corn – Jun 6 – Jul 4 –
Basil May 2 – 16 Jun 13 – 20 –

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 June 6May 23May 6
Fall frost before September 24October 5October 19

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 May 8 (May 28 in a late year), and the first one in fall around October 16.

Where these dates come from

NOAA weather station HEBER (BLACK MESA) RS, AZ US (USC00023961), 1991–2020 climate normals. It's the nearest station for 5 zip codes, all within 22 miles:

85911, 85923, 85928, 85931, 85933

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