Dutton, MT 59416 Frost Dates
When can you plant in Dutton, MT?
The last spring frost here typically falls around 05/20, about 265 days from today. The first fall frost typically arrives around 09/19, about 119 frost-free days later.
The USDA Plant Hardiness Zone Map puts Dutton in Zone 4a (-30 to -25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
About 3 weeks of growing season left in Dutton before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 05/20 isn't a guarantee
05/20 is the middle of 30 years of NOAA records, not a promise. Plant by 05/09 and you're betting against frost in roughly 9 years out of 10. 06/03 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Dutton compares
Dutton's growing season runs about 119 days, ranking 39,171 of 40,283 US ZIP codes measured here, longest to shortest. Within MT, it ranks 223 of 392.
Learn more
local microclimates covers what one yard in Dutton can differ from the 59416 normal. zone vs. frost date covers why Zone 4a and Dutton's frost date answer different questions.