51.0500°N/114.0700°W
When to plant in Calgary
Alberta, Canada · Köppen Dfc — subarctic
Last spring frost
May 23
±18 days · 50% prob.
First fall frost
Sep 15
±17 days · 50% prob.
Frost-free days
115
May 23 → Sep 15
Köppen zone
Dfc
Subarctic
82/100 confidence
◇ Station-measured
Frost dates are probabilities, not guarantees — your microclimate can shift them ±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 — 115 DAYS
MAY 23
SEP 15
Full crop calendar
Nearby places
Source: NOAA GHCN-Daily · 1991–2020 normals · Köppen–Geiger classification (Beck et al. 2023) · crop windows from FAO ECOCROP references. How we calculate this →
Also see frost dates for Calgary.