Quincy, IL 63471 Frost Dates
63471, near Quincy, IL: the frost window
Around 04/11 is the usual last spring frost, about 226 days away. Fall's first freeze usually shows up around 10/23, roughly 194 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Quincy 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
Quincy'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.
Why 04/11 isn't a guarantee
04/11 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.
Quincy against the rest of the dataset
About 194 days separate Quincy's last and first frost, putting it 19,430 of 40,283 ZIP codes nationally. Within IL, it ranks 358 of 1,548.
Learn more
Two guides worth reading on 63471: local microclimates, on what one yard in Quincy can differ from the 63471 normal, and zone vs. frost date, on why Zone 6a and Quincy's frost date answer different questions.