Colchester, IL 62326 Frost Dates
Frost dates for Colchester, IL, ZIP 62326
The last spring frost here typically falls around 04/13, about 228 days from today. The first fall frost typically arrives around 10/22, about 191 frost-free days later.
The USDA Plant Hardiness Zone Map puts Colchester in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 6a around Colchester has about 8 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Colchester's last frost
04/13 is the middle of 30 years of NOAA records, not a promise. Plant by 03/30 and you're betting against frost in roughly 9 years out of 10. 04/30 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Colchester compares
About 191 days separate Colchester's last and first frost, putting it 20,828 of 40,283 ZIP codes nationally. Within IL, it ranks 453 of 1,548.
Learn more
local microclimates explains what one yard in Colchester can differ from the 62326 normal, and zone vs. frost date explains why Zone 6a and Colchester's frost date answer different questions.