FrostDateCheck

Boise City, ID 83706 Frost Dates

83706, near Boise City, ID: the frost window

Zone 7a

Typically, the last spring freeze lands around 04/24, roughly 239 days out. Fall's first freeze usually shows up around 10/21, roughly 179 days after the last spring frost.

Boise City sits in USDA Zone 7a (0 to 5°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.

Stretching the season past the first frost

Boise City's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.

Why 04/24 isn't a guarantee

04/24 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/09 and only about 1 year in 10 sees frost after that.

Boise City against the rest of the dataset

About 179 days separate Boise City's last and first frost, putting it 25,135 of 40,283 ZIP codes nationally. Within ID, it ranks 14 of 320.

Learn more

Two guides worth reading on 83706: the frost range, on how to read the range around Boise City's dates instead of trusting one, and local microclimates, on what one yard in Boise City can differ from the 83706 normal.