Petersburg, IL 62675 Frost Dates
Frost dates for Petersburg, IL, ZIP 62675
Typically, the last spring freeze lands around 04/13, roughly 228 days out. The first fall frost typically arrives around 10/21, about 189 frost-free days later.
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 Petersburg, not a forecast for this year.
What to do before the first frost
Zone 6a around Petersburg 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 Petersburg's last frost
04/13 is the middle of 30 years of NOAA records, not a promise. Plant by 03/31 and you're betting against frost in roughly 9 years out of 10. 04/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Petersburg compares
At roughly 189 frost-free days, Petersburg places 21,606 of 40,283 ZIP codes in this dataset. Within IL, it ranks 609 of 1,548.
Learn more
the frost range explains how to read the range around Petersburg's dates instead of trusting one, and local microclimates explains what one yard in Petersburg can differ from the 62675 normal.