Hanover, IL 61041 Frost Dates
When can you plant in Hanover, IL?
Typically, the last spring freeze lands around 05/01, roughly 246 days out. The first fall frost typically arrives around 10/09, about 160 frost-free days later.
The USDA Plant Hardiness Zone Map puts Hanover in Zone 5a (-20 to -15°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 6 weeks of growing season left in Hanover 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
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/17 and you're betting against frost in roughly 9 years out of 10. 05/17 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Hanover compares
About 160 days separate Hanover's last and first frost, putting it 32,454 of 40,283 ZIP codes nationally. Within IL, it ranks 1,540 of 1,548.
Learn more
the frost range covers how to read the range around Hanover's dates instead of trusting one. local microclimates covers what one yard in Hanover can differ from the 61041 normal.