Clarence, IA 52216 Frost Dates
52216, near Clarence, IA: the frost window
Around 04/27 is the usual last spring frost, about 242 days away. Fall's first freeze usually shows up around 10/10, roughly 165 days after the last spring frost.
Zone 5a (-20 to -15°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Clarence, not a forecast for this year.
Stretching the season past the first frost
Clarence'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 04/27 isn't a guarantee
04/27 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 05/13 and only about 1 year in 10 sees frost after that.
Clarence against the rest of the dataset
At roughly 165 frost-free days, Clarence places 30,644 of 40,283 ZIP codes in this dataset. Within IA, it ranks 516 of 1,042.
Learn more
Two guides worth reading on 52216: the frost range, on how to read the range around Clarence's dates instead of trusting one, and local microclimates, on what one yard in Clarence can differ from the 52216 normal.