Plainfield, IL 60544 Frost Dates
Frost dates for Plainfield, IL, ZIP 60544
Typically, the last spring freeze lands around 04/20, roughly 235 days out. The first fall frost typically arrives around 10/22, about 184 frost-free days later.
Plainfield sits in USDA Zone 5b (-15 to -10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 5b around Plainfield 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 Plainfield's last frost
04/20 is the middle of 30 years of NOAA records, not a promise. Plant by 04/07 and you're betting against frost in roughly 9 years out of 10. 05/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Plainfield compares
At roughly 184 frost-free days, Plainfield places 23,419 of 40,283 ZIP codes in this dataset. Within IL, it ranks 864 of 1,548.
Learn more
zone vs. frost date explains why Zone 5b and Plainfield's frost date answer different questions, and the frost range explains how to read the range around Plainfield's dates instead of trusting one.