Last frost date in Phoenix, AZ

Average last frost
January 8

In Phoenix, the last spring frost comes around January 8 in an average year. Wait until February 12 if you want 90% odds of no more frost. The first fall frost usually arrives about December 25, which leaves 354 frost-free days. An early freeze before December 5 happens one year in ten.

Safe after (10% risk)
Feb 12
Average first frost
Dec 25
Frost-free season
354 days
Hard freeze (28°F) ends
Jan 8
Next 6 nights in Phoenix

No frost in the next 6 nights

National Weather Service forecast, updated Oct 22, 11:10 UTC

  1. ThuOct 2263°
  2. FriOct 2360°
  3. SatOct 2459°
  4. SunOct 2560°
  5. MonOct 2661°
  6. TueOct 2763°
JanFebMarAprMayJunJulAugSepOctNovDecLast frost Jan 8First frost Dec 25354 frost-free daysBlue: chance of 32°F frost. Green: average frost-free season.JFMAMJJASOND354 frost-free days
Frost risk through the year at Phoenix Deer Valley Municipal Airport, 8.0 miles from Phoenix.

Planting calendar for Phoenix

Windows count forward or back from the average frost dates above. Click a crop for dates across Arizona.

Start indoorsPlant outSow outdoorsFall plantingAverage last and first frost
Warm-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
TomatoesFeb 15–Mar 1
PumpkinsFeb 15–Mar 1
SunflowersFeb 15–Mar 8
CucumbersFeb 22–Mar 1
CornFeb 15–Mar 1
Sweet potatoesFeb 15–Mar 1
WatermelonFeb 15–Mar 1
Green beansFeb 15–Mar 8
ZucchiniFeb 15–Mar 1
OkraFeb 15–Mar 1
PeppersFeb 15–Mar 1
BasilFeb 15–Mar 1
Butternut squashFeb 15–Mar 1
CantaloupeFeb 15–Mar 1
EggplantFeb 15–Mar 1
Cool-season crops
JanFebMarAprMayJunJulAugSepOctNovDec
PotatoesDec 11–Dec 25
OnionsNov 27–Dec 18
CarrotsDec 18–Jan 22
LettuceDec 25–Jan 15
BroccoliDec 11–Dec 25
BeetsDec 11–Jan 22
PeasNov 27–Dec 11
CabbageDec 11–Dec 25
RadishesDec 4–Jan 15
Brussels sproutsDec 25–Jan 8
SpinachNov 27–Dec 18
CilantroDec 25–Jan 15
KaleDec 11–Dec 25
Collard greensDec 11–Dec 25
TurnipsDec 11–Dec 25
DillJan 8–Jan 22
CeleryJan 15–Jan 22
CauliflowerDec 25–Jan 8
LeeksDec 25–Jan 8
Swiss chardDec 25–Jan 22
ParsleyDec 25–Jan 15
Fall bulbs and garlic
JanFebMarAprMayJunJulAugSepOctNovDec
Tulip bulbsDec 15–Jan 15
GarlicOct 15–Nov 30
Daffodil bulbsOct 15–Nov 30
Perennials
JanFebMarAprMayJunJulAugSepOctNovDec
StrawberriesDec 11–Dec 25
AsparagusDec 11–Dec 25

Frost probabilities

ThresholdSpring, 90% chance laterSpring, 50%Spring, 10%Fall, 10% chance earlierFall, 50%Fall, 90%
Light frost, 32°FDec 16Jan 8Feb 12Dec 5Dec 25Jan 23
Hard freeze, 28°FDec 15Jan 8Feb 2Dec 14Jan 7Feb 1

Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.

Where these numbers come from

NOAA station Phoenix Deer Valley Municipal Airport (USW00003184) sits 8.0 miles from the center of Phoenix at 1,455 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.

Questions

When is the last frost in Phoenix, AZ?

The average last frost date in Phoenix is January 8, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after February 12.

When is the first frost in Phoenix?

The first frost in fall usually comes around December 25. One year in ten it arrives before December 5.

How long is the growing season in Phoenix?

About 354 days between the average last and first frost.

When should I plant tomatoes in Phoenix?

Plant tomato seedlings outside from February 15 to March 1. Start seeds indoors six to eight weeks earlier.

Nearby in Arizona

All 30 cities in Arizona