FrostDateCheck

Chicago, IL 60661 Frost Dates

When can you plant in Chicago, IL?

Zone 6b

Typically, the last spring freeze lands around 04/10, roughly 225 days out. The first fall frost typically arrives around 11/05, about 208 frost-free days later.

Chicago sits in USDA Zone 6b (-5 to 0°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.

What to do before the first frost

About 10 weeks of growing season left in Chicago before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

Why 04/10 isn't a guarantee

04/10 is the middle of 30 years of NOAA records, not a promise. Plant by 03/29 and you're betting against frost in roughly 9 years out of 10. 04/25 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Chicago compares

About 208 days separate Chicago's last and first frost, putting it 15,475 of 40,283 ZIP codes nationally. Within IL, it ranks 71 of 1,548.

Learn more

the frost range covers how to read the range around Chicago's dates instead of trusting one. local microclimates covers what one yard in Chicago can differ from the 60661 normal.