Hartwick, IA 52232 Frost Dates
Hartwick, IA: when does the frost end?
Typically, the last spring freeze lands around 04/28, roughly 243 days out. Fall's first freeze usually shows up around 10/10, roughly 165 days after the last spring frost.
Hartwick 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
With roughly 6 weeks until Hartwick's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Hartwick's last frost
04/28 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/11 and only about 1 year in 10 sees frost after that.
Hartwick against the rest of the dataset
At roughly 165 frost-free days, Hartwick places 30,784 of 40,283 ZIP codes in this dataset. Within IA, it ranks 567 of 1,042.
Learn more
Before leaning on 52232's figures: the frost range explains how to read the range around Hartwick's dates instead of trusting one, while local microclimates explains what one yard in Hartwick can differ from the 52232 normal.