When to plant kale in Portland

Kale is cold-hardy, so every date keys off Portland's frost dates of Mar 1.
Step 1 · Sow
Start seeds indoors
Jan 18 – Feb 8
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Dec 26 – Jan 16
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Feb 19 – Mar 11
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Aug 18 – Sep 1
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Oct 19 – Nov 8
Maturity window for the second sowing.
Window
Days to maturity
55 – 75 d
Portland's 266-day season leaves this much room.
Kale on Portland'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 1
NOV 22

Common questions

When can I sow kale outdoors in Portland?

Direct-sow around late December (Dec 26–Jan 16) in Portland, based on its local frost dates. Confidence 85%.

When will kale be ready to harvest in Portland?

Expect to harvest from around mid February (Feb 19–Mar 11) in Portland, based on its local frost dates. Confidence 79%.

When should I start kale seeds indoors in Portland?

Start seeds indoors around mid January (Jan 18–Feb 8) in Portland, based on its local frost dates. Confidence 84%.

When can I transplant kale outdoors in Portland?

Transplant outdoors around late December (Dec 26–Jan 16) in Portland, based on its local frost dates. Confidence 85%.

Can I plant kale in autumn in Portland?

Yes — Portland supports a second, autumn sowing of kale around mid August (Aug 18–Sep 1), timed to mature before the first fall frost.

How long is the growing season in Portland?

Portland has roughly 266 frost-free days, which is enough time to grow kale to maturity outdoors.

The rule of thumb

Sow kale 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 Portland's frost dates.

Confidence 88/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.