When to plant melon (cantaloupe/watermelon) in Montreal
Melon (cantaloupe/watermelon) is frost-tender, so every date keys off Montreal's last spring frost of May 11.
Step 1 · Sow
Start seeds indoors
Apr 20 – May 11
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 25 – Jun 15
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Aug 8 – Sep 2
Picking runs until conditions turn against the crop.
Window
Days to maturity
75 – 100 d
Montreal's 142-day season leaves this much room.
Melon (cantaloupe/watermelon) 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 melon (cantaloupe/watermelon) outdoors in Montreal?
Direct-sow around late May (May 25–Jun 15) in Montreal, based on its local frost dates. Confidence 86%.
When will melon (cantaloupe/watermelon) be ready to harvest in Montreal?
Expect to harvest from around early August (Aug 8–Sep 2) in Montreal, based on its local frost dates. Confidence 77%.
When should I start melon (cantaloupe/watermelon) seeds indoors in Montreal?
Start seeds indoors around mid April (Apr 20–May 11) in Montreal, based on its local frost dates. Confidence 82%.
When can I transplant melon (cantaloupe/watermelon) outdoors in Montreal?
Transplant outdoors around late May (May 25–Jun 15) 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 melon (cantaloupe/watermelon) to maturity outdoors.
The rule of thumb
Sow melon (cantaloupe/watermelon) 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.