Shelby, IA 51570 Frost Dates
Shelby, IA: when does the frost end?
Typically, the last spring freeze lands around 04/27, roughly 242 days out. Fall's first freeze usually shows up around 10/09, roughly 165 days after the last spring frost.
Shelby sits in USDA Zone 5b (-15 to -10°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
With roughly 6 weeks until Shelby'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
04/27 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/12 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/09 and only about 1 year in 10 sees frost after that.
Shelby against the rest of the dataset
At roughly 165 frost-free days, Shelby places 30,666 of 40,283 ZIP codes in this dataset. Within IA, it ranks 529 of 1,042.
Learn more
Before leaning on 51570's figures: local microclimates explains what one yard in Shelby can differ from the 51570 normal, while zone vs. frost date explains why Zone 5b and Shelby's frost date answer different questions.