When to plant summer squash / zucchini in Louisville

Summer squash / Zucchini is frost-tender, so every date keys off Louisville's last spring frost of Apr 1.
Step 1 · Sow
Start seeds indoors
Apr 3 – Apr 24
Before your last frost, on a warm windowsill or heat mat.
Step 2 · Plant
Transplant outdoors
Apr 28 – May 19
Once frost risk has passed and nights stay mild.
Step 3 · Harvest
Harvest window
Jun 12 – Jun 27
Picking runs until conditions turn against the crop.
Window
Days to maturity
45 – 60 d
Louisville's 212-day season leaves this much room.
Summer squash / Zucchini on Louisville'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 1
OCT 29

Common questions

When can I sow summer squash / zucchini outdoors in Louisville?

Direct-sow around late April (Apr 28–May 19) in Louisville, based on its local frost dates. Confidence 80%.

When will summer squash / zucchini be ready to harvest in Louisville?

Expect to harvest from around mid June (Jun 12–Jun 27) in Louisville, based on its local frost dates. Confidence 74%.

When should I start summer squash / zucchini seeds indoors in Louisville?

Start seeds indoors around early April (Apr 3–Apr 24) in Louisville, based on its local frost dates. Confidence 78%.

When can I transplant summer squash / zucchini outdoors in Louisville?

Transplant outdoors around late April (Apr 28–May 19) in Louisville, based on its local frost dates. Confidence 80%.

How long is the growing season in Louisville?

Louisville has roughly 212 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 Louisville's frost dates.

Confidence 82/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.