Winnebago, IL 61110 Frost Dates
When can you plant in Winnebago, IL?
Typically, the last spring freeze lands around 04/24, roughly 239 days out. The first fall frost typically arrives around 10/17, about 174 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 Winnebago, not a forecast for this year.
What to do before the first frost
About 7 weeks of growing season left in Winnebago 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
04/24 is the middle of 30 years of NOAA records, not a promise. Plant by 04/10 and you're betting against frost in roughly 9 years out of 10. 05/08 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Winnebago compares
At roughly 174 frost-free days, Winnebago places 27,480 of 40,283 ZIP codes in this dataset. Within IL, it ranks 1,237 of 1,548.
Learn more
local microclimates covers what one yard in Winnebago can differ from the 61110 normal. zone vs. frost date covers why Zone 5b and Winnebago's frost date answer different questions.