Ennis, MT 59729 Frost Dates
When can you plant in Ennis, MT?
Typically, the last spring freeze lands around 06/16, roughly 292 days out. The first fall frost typically arrives around 09/04, about 78 frost-free days later.
Ennis sits in USDA Zone 5a (-20 to -15°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.
What to do before the first frost
About 1 week of growing season left in Ennis before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
How much risk comes with planting early here
06/16 is the middle of 30 years of NOAA records, not a promise. Plant by 05/30 and you're betting against frost in roughly 9 years out of 10. 07/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Ennis compares
At roughly 78 frost-free days, Ennis places 40,064 of 40,283 ZIP codes in this dataset. Within MT, it ranks 366 of 392.
Learn more
the frost range covers how to read the range around Ennis's dates instead of trusting one. local microclimates covers what one yard in Ennis can differ from the 59729 normal.