Bullhead City, AZ 89039 Frost Dates
89039, near Bullhead City, AZ: the frost window
Typically, the last spring freeze lands around 03/07, roughly 191 days out. Fall's first freeze usually shows up around 11/29, roughly 266 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Bullhead City in Zone 9a (20 to 25°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
Bullhead City's growing season runs out in roughly 13 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
03/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/08 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/10 and only about 1 year in 10 sees frost after that.
Bullhead City against the rest of the dataset
Bullhead City's growing season runs about 266 days, ranking 5,916 of 40,283 US ZIP codes measured here, longest to shortest. Within AZ, it ranks 310 of 506.
Learn more
Two guides worth reading on 89039: local microclimates, on what one yard in Bullhead City can differ from the 89039 normal, and zone vs. frost date, on why Zone 9a and Bullhead City's frost date answer different questions.