Luther, IA 50152 Frost Dates
Luther, IA: when does the frost end?
Around 04/23 is the usual last spring frost, about 238 days away. Fall's first freeze usually shows up around 10/14, roughly 173 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Luther in Zone 5a (-20 to -15°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
With roughly 7 weeks until Luther's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
04/23 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 05/05 and only about 1 year in 10 sees frost after that.
Luther against the rest of the dataset
About 173 days separate Luther's last and first frost, putting it 28,098 of 40,283 ZIP codes nationally. Within IA, it ranks 261 of 1,042.
Learn more
Before leaning on 50152's figures: zone vs. frost date explains why Zone 5a and Luther's frost date answer different questions, while the frost range explains how to read the range around Luther's dates instead of trusting one.