Mount Kisco, NY 10518 Frost Dates
10518, near Mount Kisco, NY: the frost window
Around 05/01 is the usual last spring frost, about 246 days away. Fall's first freeze usually shows up around 10/14, roughly 166 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Mount Kisco in Zone 6b (-5 to 0°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
Mount Kisco's growing season runs out in roughly 7 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/01 isn't a guarantee
05/01 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/18 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/16 and only about 1 year in 10 sees frost after that.
Mount Kisco against the rest of the dataset
Mount Kisco's growing season runs about 166 days, ranking 30,317 of 40,283 US ZIP codes measured here, longest to shortest. Within NY, it ranks 872 of 1,951.
Learn more
Two guides worth reading on 10518: local microclimates, on what one yard in Mount Kisco can differ from the 10518 normal, and zone vs. frost date, on why Zone 6b and Mount Kisco's frost date answer different questions.