Glen Carbon, IL 62034 Frost Dates
When can you plant in Glen Carbon, IL?
Around 04/04 is the usual last spring frost, about 219 days away. The first fall frost typically arrives around 11/05, about 214 frost-free days later.
The USDA Plant Hardiness Zone Map puts Glen Carbon in Zone 7a (0 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
About 10 weeks of growing season left in Glen Carbon before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
The actual range around Glen Carbon's last frost
04/04 is the middle of 30 years of NOAA records, not a promise. Plant by 03/18 and you're betting against frost in roughly 9 years out of 10. 04/19 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Glen Carbon compares
About 214 days separate Glen Carbon's last and first frost, putting it 14,232 of 40,283 ZIP codes nationally. Within IL, it ranks 11 of 1,548.
Learn more
zone vs. frost date covers why Zone 7a and Glen Carbon's frost date answer different questions. the frost range covers how to read the range around Glen Carbon's dates instead of trusting one.