When to plant melon (cantaloupe/watermelon) in Washington

Melon (cantaloupe/watermelon) is frost-tender, so every date keys off Washington's last spring frost of Mar 24.
Step 1 · Sow
Start seeds indoors
Mar 17 – Apr 7
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Jun 3 – Jun 24
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Aug 17 – Sep 11
Picking runs until conditions turn against the crop.
Window
Days to maturity
75 – 100 d
Washington's 234-day season leaves this much room.
Melon (cantaloupe/watermelon) on Washington'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
MAR 24
NOV 17

Common questions

When can I sow melon (cantaloupe/watermelon) outdoors in Washington?

Direct-sow around early June (Jun 3–Jun 24) in Washington, based on its local frost dates. Confidence 86%.

When will melon (cantaloupe/watermelon) be ready to harvest in Washington?

Expect to harvest from around mid August (Aug 17–Sep 11) in Washington, based on its local frost dates. Confidence 80%.

When should I start melon (cantaloupe/watermelon) seeds indoors in Washington?

Start seeds indoors around mid March (Mar 17–Apr 7) in Washington, based on its local frost dates. Confidence 85%.

When can I transplant melon (cantaloupe/watermelon) outdoors in Washington?

Transplant outdoors around early June (Jun 3–Jun 24) in Washington, based on its local frost dates. Confidence 86%.

How long is the growing season in Washington?

Washington has roughly 234 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 Washington's frost dates.

Confidence 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.