Boise City, ID 83707 Frost Dates
Frost dates for Boise City, ID, ZIP 83707
Around 04/30 is the usual last spring frost, about 245 days away. The first fall frost typically arrives around 10/22, about 173 frost-free days later.
Zone 7a (0 to 5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Boise City, not a forecast for this year.
What to do before the first frost
Zone 7a around Boise City has about 8 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Boise City's last frost
04/30 is the middle of 30 years of NOAA records, not a promise. Plant by 04/11 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Boise City compares
About 173 days separate Boise City's last and first frost, putting it 27,667 of 40,283 ZIP codes nationally. Within ID, it ranks 52 of 320.
Learn more
zone vs. frost date explains why Zone 7a and Boise City's frost date answer different questions, and the frost range explains how to read the range around Boise City's dates instead of trusting one.