Ankeny, IA 50021 Frost Dates
When can you plant in Ankeny, IA?
Typically, the last spring freeze lands around 04/23, roughly 238 days out. The first fall frost typically arrives around 10/15, about 173 frost-free days later.
The USDA Plant Hardiness Zone Map puts Ankeny 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 7 weeks of growing season left in Ankeny before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/23 isn't a guarantee
04/23 is the middle of 30 years of NOAA records, not a promise. Plant by 04/08 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 Ankeny compares
Ankeny's growing season runs about 173 days, ranking 27,686 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 212 of 1,042.
Learn more
zone vs. frost date covers why Zone 5b and Ankeny's frost date answer different questions. the frost range covers how to read the range around Ankeny's dates instead of trusting one.