When to plant lettuce in Duluth

Lettuce is cold-hardy, so every date keys off Duluth's frost dates of May 10.
Step 1 · Sow
Start seeds indoors
Apr 12 – May 3
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Apr 22 – May 13
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 6 – Jun 21
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Jul 5 – Jul 19
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Aug 26 – Sep 10
Maturity window for the second sowing.
Window
Days to maturity
45 – 60 d
Duluth's 150-day season leaves this much room.
Lettuce 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 lettuce outdoors in Duluth?

Direct-sow around late April (Apr 22–May 13) in Duluth, based on its local frost dates. Confidence 84%.

When will lettuce be ready to harvest in Duluth?

Expect to harvest from around early June (Jun 6–Jun 21) in Duluth, based on its local frost dates. Confidence 78%.

When should I start lettuce seeds indoors in Duluth?

Start seeds indoors around mid April (Apr 12–May 3) in Duluth, based on its local frost dates. Confidence 83%.

When can I transplant lettuce outdoors in Duluth?

Transplant outdoors around late April (Apr 22–May 13) in Duluth, based on its local frost dates. Confidence 84%.

Can I plant lettuce in autumn in Duluth?

Yes — Duluth supports a second, autumn sowing of lettuce around early July (Jul 5–Jul 19), 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 lettuce to maturity outdoors.

The rule of thumb

Sow lettuce 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.