When to plant cauliflower in Calgary
Cauliflower is cold-hardy, so every date keys off Calgary's frost dates of May 23.
Step 1 · Sow
Start seeds indoors
Apr 11 – May 2
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 9 – May 30
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jul 8 – Aug 2
Picking runs until conditions turn against the crop.
Window
Days to maturity
60 – 85 d
Calgary's 115-day season leaves this much room.
Cauliflower on Calgary's 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
MAY 23
SEP 15
Common questions
When will cauliflower be ready to harvest in Calgary?
Expect to harvest from around early July (Jul 8–Aug 2) in Calgary, based on its local frost dates. Confidence 74%.
When should I start cauliflower seeds indoors in Calgary?
Start seeds indoors around mid April (Apr 11–May 2) in Calgary, based on its local frost dates. Confidence 78%.
When can I transplant cauliflower outdoors in Calgary?
Transplant outdoors around early May (May 9–May 30) in Calgary, based on its local frost dates. Confidence 82%.
How long is the growing season in Calgary?
Calgary has roughly 115 frost-free days, which is enough time to grow cauliflower to maturity outdoors.
The rule of thumb
Sow cauliflower as soon as the soil is workable — it tolerates cool weather and light frost. Every date on this page is derived from that rule and Calgary's frost dates.
Confidence 82/100 · NOAA GHCN-Daily · 1991–2020 normals · frost dates are probabilities, not guarantees.