Blue Island, IL 60406 Frost Dates
60406, near Blue Island, IL: the frost window
Typically, the last spring freeze lands around 04/10, roughly 225 days out. Fall's first freeze usually shows up around 11/01, roughly 203 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Blue Island in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Blue Island's growing season runs out in roughly 9 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/10 isn't a guarantee
04/10 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/30 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/26 and only about 1 year in 10 sees frost after that.
Blue Island against the rest of the dataset
Blue Island's growing season runs about 203 days, ranking 16,855 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 150 of 1,548.
Learn more
Two guides worth reading on 60406: zone vs. frost date, on why Zone 6a and Blue Island's frost date answer different questions, and the frost range, on how to read the range around Blue Island's dates instead of trusting one.