46.8721°N/113.9940°W
When to plant in Missoula
Montana, United States · Continental, dry warm summer (Köppen Dsb)
Last spring frost · safe
May 26
~10% frost risk · typical May 15
First fall frost · safe
Sep 14
~10% frost risk · typical Oct 4
Frost-free days
138
May 15 → Oct 4
Climate zone
Continental, dry warm summer
Köppen Dsb
83/100 confidence
◇ Station-based
The frost date shown is the safe date (~10% frost risk); the typical median is shown alongside. Your microclimate can shift things ±1–2 weeks.
The growing year
Frost-bounded season with crops mapped onto the 12-month axis.
Frost risk Growing Harvest
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
NOV
DEC
FROST
FROST
GROWING SEASON — 138 DAYS
MAY 15
OCT 4
Full crop calendar
Same climate — Continental, dry warm summer
Source: Curated · based on NOAA GHCN-Daily 1991–2020 normal · Köppen–Geiger classification (Beck et al. 2023) · crop windows from FAO ECOCROP references. How we calculate this →
Also see frost dates for Missoula.