When to plant tomato in Chicago
Tomato is frost-tender, so every date keys off Chicago's last spring frost of Apr 10.
Step 1 · Sow
Start seeds indoors
Mar 7 – Mar 28
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 18 – Jun 8
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jul 17 – Aug 11
Picking runs until conditions turn against the crop.
Window
Days to maturity
60 – 85 d
Chicago's 206-day season leaves this much room.
Tomato 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
FROST
FROST
APR 10
OCT 31
Common questions
When will tomato be ready to harvest in Chicago?
Expect to harvest from around mid July (Jul 17–Aug 11) in Chicago, based on its local frost dates. Confidence 76%.
When should I start tomato seeds indoors in Chicago?
Start seeds indoors around early March (Mar 7–Mar 28) in Chicago, based on its local frost dates. Confidence 80%.
When can I transplant tomato outdoors in Chicago?
Transplant outdoors around mid May (May 18–Jun 8) in Chicago, based on its local frost dates. Confidence 81%.
How long is the growing season in Chicago?
Chicago has roughly 206 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 Chicago's frost dates.
Confidence 84/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.