Decatur, IL 62521 Frost Dates
Decatur, IL: when does the frost end?
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.
Zone 6a (-10 to -5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Decatur, not a forecast for this year.
Stretching the season past the first frost
With roughly 8 weeks until Decatur's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
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
At roughly 192 frost-free days, Decatur places 20,141 of 40,283 ZIP codes in this dataset. Within IL, it ranks 416 of 1,548.
Learn more
Before leaning on 62521's figures: the frost range explains how to read the range around Decatur's dates instead of trusting one, while local microclimates explains what one yard in Decatur can differ from the 62521 normal.