When to plant lettuce in Chicago

Lettuce is cold-hardy, so every date keys off Chicago's frost dates of Apr 10.
Step 1 · Sow
Start seeds indoors
Mar 13 – Apr 3
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Mar 24 – Apr 14
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
May 8 – May 23
Picking runs until conditions turn against the crop.
Step 4 · Second sowing
Autumn / second sowing
Jul 20 – Aug 3
A second window for a fall crop, timed to mature before the first frost.
Step 5 · Second harvest
Autumn crop harvest
Sep 10 – Sep 25
Maturity window for the second sowing.
Window
Days to maturity
45 – 60 d
Chicago's 206-day season leaves this much room.
Lettuce on Chicago'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
APR 10
OCT 31

Common questions

When can I sow lettuce outdoors in Chicago?

Direct-sow around late March (Mar 24–Apr 14) in Chicago, based on its local frost dates. Confidence 81%.

When will lettuce be ready to harvest in Chicago?

Expect to harvest from around early May (May 8–May 23) in Chicago, based on its local frost dates. Confidence 76%.

When should I start lettuce seeds indoors in Chicago?

Start seeds indoors around mid March (Mar 13–Apr 3) in Chicago, based on its local frost dates. Confidence 80%.

When can I transplant lettuce outdoors in Chicago?

Transplant outdoors around late March (Mar 24–Apr 14) in Chicago, based on its local frost dates. Confidence 81%.

Can I plant lettuce in autumn in Chicago?

Yes — Chicago supports a second, autumn sowing of lettuce around mid July (Jul 20–Aug 3), timed to mature before the first fall frost.

How long is the growing season in Chicago?

Chicago has roughly 206 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 Chicago's frost dates.

Confidence 84/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.