Tucson, AZ 85734 Frost Dates
Frost dates for Tucson, AZ, ZIP 85734
The last spring frost here typically falls around 02/05, about 161 days from today. The first fall frost typically arrives around 12/09, about 307 frost-free days later.
Tucson sits in USDA Zone 9a (20 to 25°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
Zone 9a around Tucson has about 15 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
How much risk comes with planting early here
02/05 is the middle of 30 years of NOAA records, not a promise. Plant by 01/04 and you're betting against frost in roughly 9 years out of 10. 03/02 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Tucson compares
Tucson's growing season runs about 307 days, ranking 3,671 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 236 of 506.
Learn more
zone vs. frost date explains why Zone 9a and Tucson's frost date answer different questions, and the frost range explains how to read the range around Tucson's dates instead of trusting one.