When to plant tomato in Washington
Tomato is frost-tender, so every date keys off Washington's last spring frost of Mar 24.
Step 1 · Sow
Start seeds indoors
Feb 24 – Mar 17
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Apr 30 – May 21
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 29 – Jul 24
Picking runs until conditions turn against the crop.
Window
Days to maturity
60 – 85 d
Washington's 234-day season leaves this much room.
Tomato 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 tomato be ready to harvest in Washington?
Expect to harvest from around late June (Jun 29–Jul 24) in Washington, based on its local frost dates. Confidence 80%.
When should I start tomato seeds indoors in Washington?
Start seeds indoors around late February (Feb 24–Mar 17) in Washington, based on its local frost dates. Confidence 85%.
When can I transplant tomato outdoors in Washington?
Transplant outdoors around late April (Apr 30–May 21) 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 tomato to maturity outdoors.
The rule of thumb
Sow tomato 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.