When to plant summer squash / zucchini in Pittsburgh
Summer squash / Zucchini is frost-tender, so every date keys off Pittsburgh's last spring frost of Apr 17.
Step 1 · Sow
Start seeds indoors
Apr 15 – May 6
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
May 11 – Jun 1
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 25 – Jul 10
Picking runs until conditions turn against the crop.
Window
Days to maturity
45 – 60 d
Pittsburgh's 188-day season leaves this much room.
Summer squash / Zucchini on Pittsburgh'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 17
OCT 25
Common questions
When can I sow summer squash / zucchini outdoors in Pittsburgh?
Direct-sow around mid May (May 11–Jun 1) in Pittsburgh, based on its local frost dates. Confidence 79%.
When will summer squash / zucchini be ready to harvest in Pittsburgh?
Expect to harvest from around late June (Jun 25–Jul 10) in Pittsburgh, based on its local frost dates. Confidence 73%.
When should I start summer squash / zucchini seeds indoors in Pittsburgh?
Start seeds indoors around mid April (Apr 15–May 6) in Pittsburgh, based on its local frost dates. Confidence 77%.
When can I transplant summer squash / zucchini outdoors in Pittsburgh?
Transplant outdoors around mid May (May 11–Jun 1) in Pittsburgh, based on its local frost dates. Confidence 79%.
How long is the growing season in Pittsburgh?
Pittsburgh has roughly 188 frost-free days, which is enough time to grow summer squash / zucchini to maturity outdoors.
The rule of thumb
Sow summer squash / zucchini 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 Pittsburgh's frost dates.
Confidence 81/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.