Ames, IA 50013 Frost Dates
50013, near Ames, IA: the frost window
Around 04/26 is the usual last spring frost, about 241 days away. Fall's first freeze usually shows up around 10/08, roughly 164 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Ames in Zone 5b (-15 to -10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Ames's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/26 isn't a guarantee
04/26 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/09 and only about 1 year in 10 sees frost after that.
Ames against the rest of the dataset
Ames's growing season runs about 164 days, ranking 30,829 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 575 of 1,042.
Learn more
Two guides worth reading on 50013: local microclimates, on what one yard in Ames can differ from the 50013 normal, and zone vs. frost date, on why Zone 5b and Ames's frost date answer different questions.