Coulterville, IL 62237 Frost Dates
62237, near Coulterville, IL: the frost window
Around 04/12 is the usual last spring frost, about 227 days away. Fall's first freeze usually shows up around 10/22, roughly 191 days after the last spring frost.
Zone 6b (-5 to 0°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 Coulterville, not a forecast for this year.
Stretching the season past the first frost
Coulterville'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.
How much risk comes with planting early here
04/12 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/29 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/29 and only about 1 year in 10 sees frost after that.
Coulterville against the rest of the dataset
About 191 days separate Coulterville's last and first frost, putting it 20,848 of 40,283 ZIP codes nationally. Within IL, it ranks 457 of 1,548.
Learn more
Two guides worth reading on 62237: the frost range, on how to read the range around Coulterville's dates instead of trusting one, and local microclimates, on what one yard in Coulterville can differ from the 62237 normal.