FrostDateCheck

Panama, IA 51562 Frost Dates

51562, near Panama, IA: the frost window

Zone 5b

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.

Panama 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

Panama'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 04/27 isn't a guarantee

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.

Panama against the rest of the dataset

At roughly 165 frost-free days, Panama places 30,749 of 40,283 ZIP codes in this dataset. Within IA, it ranks 550 of 1,042.

Learn more

Two guides worth reading on 51562: the frost range, on how to read the range around Panama's dates instead of trusting one, and local microclimates, on what one yard in Panama can differ from the 51562 normal.