When to plant leek in Washington
Leek is cold-hardy, so every date keys off Washington's frost dates of Mar 24.
Step 1 · Sow
Start seeds indoors
Jan 13 – Feb 3
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 12 – Apr 2
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 20 – Jul 10
Picking runs until conditions turn against the crop.
Window
Days to maturity
100 – 120 d
Washington's 234-day season leaves this much room.
Leek 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
FROST
FROST
MAR 24
NOV 17
Common questions
When will leek be ready to harvest in Washington?
Expect to harvest from around mid June (Jun 20–Jul 10) in Washington, based on its local frost dates. Confidence 80%.
When should I start leek seeds indoors in Washington?
Start seeds indoors around mid January (Jan 13–Feb 3) in Washington, based on its local frost dates. Confidence 85%.
When can I transplant leek outdoors in Washington?
Transplant outdoors around mid March (Mar 12–Apr 2) 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 leek to maturity outdoors.
The rule of thumb
Sow leek 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 Washington's frost dates.
Confidence 89/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.