When to plant summer squash / zucchini in Montreal
Summer squash / Zucchini is frost-tender, so every date keys off Montreal's last spring frost of May 11.
Step 1 · Sow
Start seeds indoors
Apr 27 – May 18
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 18 – Jun 8
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jul 2 – Jul 17
Picking runs until conditions turn against the crop.
Window
Days to maturity
45 – 60 d
Montreal's 142-day season leaves this much room.
Summer squash / Zucchini on Montreal'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 11
SEP 30
Common questions
When can I sow summer squash / zucchini outdoors in Montreal?
Direct-sow around mid May (May 18–Jun 8) in Montreal, based on its local frost dates. Confidence 86%.
When will summer squash / zucchini be ready to harvest in Montreal?
Expect to harvest from around early July (Jul 2–Jul 17) in Montreal, based on its local frost dates. Confidence 77%.
When should I start summer squash / zucchini seeds indoors in Montreal?
Start seeds indoors around late April (Apr 27–May 18) in Montreal, based on its local frost dates. Confidence 82%.
When can I transplant summer squash / zucchini outdoors in Montreal?
Transplant outdoors around mid May (May 18–Jun 8) in Montreal, based on its local frost dates. Confidence 86%.
How long is the growing season in Montreal?
Montreal has roughly 142 frost-free days, which is enough time to grow summer squash / zucchini to maturity outdoors.
The rule of thumb
Sow summer squash / zucchini 6–8 weeks before your last spring frost; plant out 2–3 weeks after it. Every date on this page is derived from that rule and Montreal's frost dates.
Confidence 86/100 · NOAA GHCN-Daily · 1991–2020 normals · frost dates are probabilities, not guarantees.