Plentywood, MT 59254 Frost Dates
59254, near Plentywood, MT: the frost window
The last spring frost here typically falls around 05/25, about 270 days from today. Fall's first freeze usually shows up around 09/14, roughly 111 days after the last spring frost.
Zone 3b (-35 to -30°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 Plentywood, not a forecast for this year.
Stretching the season past the first frost
Plentywood's growing season runs out in roughly 2 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
05/25 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/08 and only about 1 year in 10 sees frost after that.
Plentywood against the rest of the dataset
At roughly 111 frost-free days, Plentywood places 39,466 of 40,283 ZIP codes in this dataset. Within MT, it ranks 274 of 392.
Learn more
Two guides worth reading on 59254: the frost range, on how to read the range around Plentywood's dates instead of trusting one, and local microclimates, on what one yard in Plentywood can differ from the 59254 normal.