Silver City, IA 51554 Frost Dates
51554, near Silver City, IA: the frost window
Around 04/23 is the usual last spring frost, about 238 days away. Fall's first freeze usually shows up around 10/11, roughly 170 days after the last spring frost.
Zone 5b (-15 to -10°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Silver City, not a forecast for this year.
Stretching the season past the first frost
Silver City'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 04/23 isn't a guarantee
04/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/09 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/06 and only about 1 year in 10 sees frost after that.
Silver City against the rest of the dataset
At roughly 170 frost-free days, Silver City places 29,230 of 40,283 ZIP codes in this dataset. Within IA, it ranks 319 of 1,042.
Learn more
Two guides worth reading on 51554: the frost range, on how to read the range around Silver City's dates instead of trusting one, and local microclimates, on what one yard in Silver City can differ from the 51554 normal.