Moorhead, IA 51558 Frost Dates
51558, near Moorhead, IA: the frost window
Around 04/25 is the usual last spring frost, about 240 days away. Fall's first freeze usually shows up around 10/12, roughly 170 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Moorhead 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
Moorhead'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 04/25 isn't a guarantee
04/25 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 05/07 and only about 1 year in 10 sees frost after that.
Moorhead against the rest of the dataset
About 170 days separate Moorhead's last and first frost, putting it 29,246 of 40,283 ZIP codes nationally. Within IA, it ranks 322 of 1,042.
Learn more
Two guides worth reading on 51558: the frost range, on how to read the range around Moorhead's dates instead of trusting one, and local microclimates, on what one yard in Moorhead can differ from the 51558 normal.