Cedar Rapids, IA 52401 Frost Dates
52401, near Cedar Rapids, IA: the frost window
Typically, the last spring freeze lands around 04/28, roughly 243 days out. Fall's first freeze usually shows up around 10/12, roughly 166 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Cedar Rapids 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
Cedar Rapids'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 04/28 isn't a guarantee
04/28 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/13 and only about 1 year in 10 sees frost after that.
Cedar Rapids against the rest of the dataset
At roughly 166 frost-free days, Cedar Rapids places 30,263 of 40,283 ZIP codes in this dataset. Within IA, it ranks 438 of 1,042.
Learn more
Two guides worth reading on 52401: zone vs. frost date, on why Zone 5b and Cedar Rapids's frost date answer different questions, and the frost range, on how to read the range around Cedar Rapids's dates instead of trusting one.