FrostDateCheck

Plainfield, IL 60586 Frost Dates

When can you plant in Plainfield, IL?

Zone 5b

Around 04/20 is the usual last spring frost, about 235 days away. The first fall frost typically arrives around 10/22, about 184 frost-free days later.

Zone 5b (-15 to -10°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 Plainfield, not a forecast for this year.

What to do before the first frost

About 8 weeks of growing season left in Plainfield before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.

How much risk comes with planting early here

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

About 184 days separate Plainfield's last and first frost, putting it 23,421 of 40,283 ZIP codes nationally. Within IL, it ranks 866 of 1,548.

Learn more

zone vs. frost date covers why Zone 5b and Plainfield's frost date answer different questions. the frost range covers how to read the range around Plainfield's dates instead of trusting one.