Chicago, IL 60690 Frost Dates
When can you plant in Chicago, IL?
Typically, the last spring freeze lands around 04/11, roughly 226 days out. The first fall frost typically arrives around 10/31, about 201 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 9 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 04/11 isn't a guarantee
04/11 is the middle of 30 years of NOAA records, not a promise. Plant by 03/30 and you're betting against frost in roughly 9 years out of 10. 04/27 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Chicago compares
At roughly 201 frost-free days, Chicago places 17,434 of 40,283 ZIP codes in this dataset. Within IL, it ranks 228 of 1,548.
Learn more
local microclimates covers what one yard in Chicago can differ from the 60690 normal. zone vs. frost date covers why Zone 6b and Chicago's frost date answer different questions.