Millerton, IA 50165 Frost Dates
50165, near Millerton, IA: the frost window
Typically, the last spring freeze lands around 04/21, roughly 236 days out. Fall's first freeze usually shows up around 10/19, roughly 178 days after the last spring frost.
Zone 5b (-15 to -10°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 Millerton, not a forecast for this year.
Stretching the season past the first frost
Millerton's growing season runs out in roughly 7 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Millerton's last frost
04/21 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/07 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.
Millerton against the rest of the dataset
About 178 days separate Millerton's last and first frost, putting it 25,947 of 40,283 ZIP codes nationally. Within IA, it ranks 125 of 1,042.
Learn more
Two guides worth reading on 50165: local microclimates, on what one yard in Millerton can differ from the 50165 normal, and zone vs. frost date, on why Zone 5b and Millerton's frost date answer different questions.