When to plant summer squash / zucchini in Tucson
Summer squash / Zucchini is frost-tender, so every date keys off Tucson's last spring frost of Feb 27.
Step 1 · Sow
Start seeds indoors
Mar 3 – Mar 24
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.
Window
Days to maturity
45 – 60 d
Tucson's 278-day season leaves this much room.
Summer squash / Zucchini on Tucson'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
FEB 27
NOV 27
Common questions
When can I sow summer squash / zucchini outdoors in Tucson?
Direct-sow around late March (Mar 24–Apr 14) in Tucson, based on its local frost dates. Confidence 83%.
When will summer squash / zucchini be ready to harvest in Tucson?
Expect to harvest from around early May (May 8–May 23) in Tucson, based on its local frost dates. Confidence 75%.
When should I start summer squash / zucchini seeds indoors in Tucson?
Start seeds indoors around early March (Mar 3–Mar 24) in Tucson, based on its local frost dates. Confidence 79%.
When can I transplant summer squash / zucchini outdoors in Tucson?
Transplant outdoors around late March (Mar 24–Apr 14) in Tucson, based on its local frost dates. Confidence 83%.
How long is the growing season in Tucson?
Tucson has roughly 278 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 Tucson's frost dates.
Confidence 83/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.