Clyde Park, MT 59018 Frost Dates
When can you plant in Clyde Park, MT?
Around 06/04 is the usual last spring frost, about 280 days away. The first fall frost typically arrives around 09/06, about 92 frost-free days later.
The USDA Plant Hardiness Zone Map puts Clyde Park in Zone 5a (-20 to -15°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 1 week of growing season left in Clyde Park before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 06/04 isn't a guarantee
06/04 is the middle of 30 years of NOAA records, not a promise. Plant by 05/19 and you're betting against frost in roughly 9 years out of 10. 06/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Clyde Park compares
At roughly 92 frost-free days, Clyde Park places 39,892 of 40,283 ZIP codes in this dataset. Within MT, it ranks 332 of 392.
Learn more
zone vs. frost date covers why Zone 5a and Clyde Park's frost date answer different questions. the frost range covers how to read the range around Clyde Park's dates instead of trusting one.