Boise City, ID 83724 Frost Dates
83724, near Boise City, ID: the frost window
Around 04/24 is the usual last spring frost, about 239 days away. 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.
How much risk comes with planting early here
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
At roughly 179 frost-free days, Boise City places 25,138 of 40,283 ZIP codes in this dataset. Within ID, it ranks 17 of 320.
Learn more
Two guides worth reading on 83724: 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 83724 normal.