When to plant kale in Duluth

Kale is cold-hardy, so every date keys off Duluth's frost dates of May 10.
Step 1 · Sow
Start seeds indoors
Mar 29 – Apr 19
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 2 – May 23
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 26 – Jul 16
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Jul 3 – Jul 17
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Sep 3 – Sep 23
Maturity window for the second sowing.
Window
Days to maturity
55 – 75 d
Duluth's 150-day season leaves this much room.
Kale on Duluth'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
MAY 10
OCT 7

Common questions

When can I sow kale outdoors in Duluth?

Direct-sow around early May (May 2–May 23) in Duluth, based on its local frost dates. Confidence 84%.

When will kale be ready to harvest in Duluth?

Expect to harvest from around late June (Jun 26–Jul 16) in Duluth, based on its local frost dates. Confidence 78%.

When should I start kale seeds indoors in Duluth?

Start seeds indoors around late March (Mar 29–Apr 19) in Duluth, based on its local frost dates. Confidence 83%.

When can I transplant kale outdoors in Duluth?

Transplant outdoors around early May (May 2–May 23) in Duluth, based on its local frost dates. Confidence 84%.

Can I plant kale in autumn in Duluth?

Yes — Duluth supports a second, autumn sowing of kale around early July (Jul 3–Jul 17), timed to mature before the first fall frost.

How long is the growing season in Duluth?

Duluth has roughly 150 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 Duluth's frost dates.

Confidence 87/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.