Philo, IL 61864 Frost Dates
Frost dates for Philo, IL, ZIP 61864
Typically, the last spring freeze lands around 04/19, roughly 234 days out. The first fall frost typically arrives around 10/17, about 180 frost-free days later.
Philo sits in USDA Zone 6a (-10 to -5°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 6a around Philo has about 7 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 Philo's last frost
04/19 is the middle of 30 years of NOAA records, not a promise. Plant by 04/06 and you're betting against frost in roughly 9 years out of 10. 05/05 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Philo compares
Philo's growing season runs about 180 days, ranking 24,921 of 40,283 US ZIP codes measured here, longest to shortest. Within IL, it ranks 963 of 1,548.
Learn more
zone vs. frost date explains why Zone 6a and Philo's frost date answer different questions, and the frost range explains how to read the range around Philo's dates instead of trusting one.