Phoenix, AZ 85051 Frost Dates
85051, near Phoenix, AZ: the frost window
The last spring frost here typically falls around 01/08, about 133 days from today. Fall's first freeze usually shows up around 12/25, roughly 354 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Phoenix in Zone 9b (25 to 30°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Phoenix's growing season runs out in roughly 17 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
01/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/16 and only about 1 year in 10 sees frost after that.
Phoenix against the rest of the dataset
About 354 days separate Phoenix's last and first frost, putting it 2,157 of 40,283 ZIP codes nationally. Within AZ, it ranks 45 of 506.
Learn more
Two guides worth reading on 85051: the frost range, on how to read the range around Phoenix's dates instead of trusting one, and local microclimates, on what one yard in Phoenix can differ from the 85051 normal.