Deep River, IA 52222 Frost Dates
When can you plant in Deep River, IA?
Typically, the last spring freeze lands around 04/28, roughly 243 days out. The first fall frost typically arrives around 10/09, about 164 frost-free days later.
The USDA Plant Hardiness Zone Map puts Deep River in Zone 5b (-15 to -10°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 Deep River 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
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/14 and you're betting against frost in roughly 9 years out of 10. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Deep River compares
About 164 days separate Deep River's last and first frost, putting it 31,200 of 40,283 ZIP codes nationally. Within IA, it ranks 629 of 1,042.
Learn more
zone vs. frost date covers why Zone 5b and Deep River's frost date answer different questions. the frost range covers how to read the range around Deep River's dates instead of trusting one.