Killdeer, ND 58642 Frost Dates
Killdeer, ND: when does the frost end?
Around 05/21 is the usual last spring frost, about 266 days away. Fall's first freeze usually shows up around 09/23, roughly 124 days after the last spring frost.
Killdeer sits in USDA Zone 4a (-30 to -25°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 4 weeks until Killdeer's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
Why 05/21 isn't a guarantee
05/21 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/09 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/05 and only about 1 year in 10 sees frost after that.
Killdeer against the rest of the dataset
Killdeer's growing season runs about 124 days, ranking 38,854 of 40,283 US ZIP codes measured here, longest to shortest. Within ND, it ranks 366 of 405.
Learn more
Before leaning on 58642's figures: the frost range explains how to read the range around Killdeer's dates instead of trusting one, while local microclimates explains what one yard in Killdeer can differ from the 58642 normal.