Frost Report

All states Oklahoma

Frost dates for Fort Supply, OK

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 21

typical year

Safe to plant

May 5

frost is over in 9 of 10 years

First fall frost

October 19

typical year

Growing season

179 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 24 – Apr 7 –
Spinach – Mar 10 – 31 Aug 24 – Sep 7
Lettuce – Mar 24 – Apr 14 Aug 24 – Sep 7
Radishes – Mar 24 – May 5 Sep 7 – 21
Onions – Mar 24 – Apr 7 –
Potatoes – Mar 31 – Apr 14 –
Carrots – Mar 31 – Apr 21 Jul 27 – Aug 10
Beets – Mar 24 – Apr 7 Aug 10 – 24
Kale Feb 10 – 24 Mar 24 – Apr 7 Aug 10 – 24
Broccoli Feb 10 – 24 Apr 7 – 21 Aug 10 – 24
Cabbage Jan 27 – Feb 10 Mar 24 – Apr 7 Aug 10 – 24
Garlic – – Sep 7 – 28
Warm-season crops
Tomatoes Mar 10 – 24 May 5 – 19 –
Peppers Mar 3 – 17 May 12 – 26 –
Cucumbers – May 5 – 26 –
Zucchini – May 5 – Jun 2 –
Pumpkins – May 5 – 26 –
Green beans – May 5 – Aug 10 –
Sweet corn – May 5 – Jun 2 –
Basil Mar 31 – Apr 14 May 12 – 19 –

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 5April 21April 8
Fall frost before October 4October 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 11 (April 27 in a late year), and the first one in fall around October 28.

Towns that use these dates

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

Fort Supply, May

Where these dates come from

NOAA weather station FT SUPPLY 3SE, OK US (USC00343304), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 14 miles:

73841, 73851

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