FrostDateCheck

Jolley, IA 50551 Frost Dates

50551, near Jolley, IA: the frost window

Zone 5a

Around 04/26 is the usual last spring frost, about 241 days away. Fall's first freeze usually shows up around 10/10, roughly 167 days after the last spring frost.

Jolley sits in USDA Zone 5a (-20 to -15°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.

Stretching the season past the first frost

Jolley'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 05/06 and only about 1 year in 10 sees frost after that.

Jolley against the rest of the dataset

Jolley's growing season runs about 167 days, ranking 30,256 of 40,283 US ZIP codes measured here, longest to shortest. Within IA, it ranks 437 of 1,042.

Learn more

Two guides worth reading on 50551: local microclimates, on what one yard in Jolley can differ from the 50551 normal, and zone vs. frost date, on why Zone 5a and Jolley's frost date answer different questions.