Pima, AZ 85543 Frost Dates
85543, near Pima, AZ: the frost window
Around 04/01 is the usual last spring frost, about 216 days away. Fall's first freeze usually shows up around 11/06, roughly 217 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Pima in Zone 8b (15 to 20°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
Pima's growing season runs out in roughly 10 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/01 isn't a guarantee
04/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/15 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/18 and only about 1 year in 10 sees frost after that.
Pima against the rest of the dataset
About 217 days separate Pima's last and first frost, putting it 13,488 of 40,283 ZIP codes nationally. Within AZ, it ranks 365 of 506.
Learn more
Two guides worth reading on 85543: the frost range, on how to read the range around Pima's dates instead of trusting one, and local microclimates, on what one yard in Pima can differ from the 85543 normal.