Phoenix, AZ 85308 Frost Dates
When can you plant in Phoenix, AZ?
The last spring frost here typically falls around 01/08, about 133 days from today. The first fall frost typically arrives around 12/25, about 354 frost-free days later.
Phoenix sits in USDA Zone 9b (25 to 30°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
About 17 weeks of growing season left in Phoenix before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
01/08 is the middle of 30 years of NOAA records, not a promise. Plant by 02/12 and you're betting against frost in roughly 9 years out of 10. 12/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Phoenix compares
About 354 days separate Phoenix's last and first frost, putting it 2,160 of 40,283 ZIP codes nationally. Within AZ, it ranks 48 of 506.
Learn more
zone vs. frost date covers why Zone 9b and Phoenix's frost date answer different questions. the frost range covers how to read the range around Phoenix's dates instead of trusting one.