Bloomington, IL 61705 Frost Dates
Frost dates for Bloomington, IL, ZIP 61705
Typically, the last spring freeze lands around 04/25, roughly 240 days out. The first fall frost typically arrives around 10/16, about 172 frost-free days later.
The USDA Plant Hardiness Zone Map puts Bloomington in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 6a around Bloomington has about 7 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 Bloomington's last frost
04/25 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. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Bloomington compares
Bloomington's growing season runs about 172 days, ranking 28,130 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 1,330 of 1,548.
Learn more
zone vs. frost date explains why Zone 6a and Bloomington's frost date answer different questions, and the frost range explains how to read the range around Bloomington's dates instead of trusting one.