Decatur, IL 62523 Frost Dates
62523, near Decatur, IL: the frost window
Around 04/14 is the usual last spring frost, about 229 days away. Fall's first freeze usually shows up around 10/24, roughly 192 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Decatur 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
Decatur's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Decatur's last frost
04/14 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/01 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/01 and only about 1 year in 10 sees frost after that.
Decatur against the rest of the dataset
Decatur's growing season runs about 192 days, ranking 20,142 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 417 of 1,548.
Learn more
Two guides worth reading on 62523: zone vs. frost date, on why Zone 6a and Decatur's frost date answer different questions, and the frost range, on how to read the range around Decatur's dates instead of trusting one.