When to plant spinach in Phoenix
Spinach is cold-hardy, so every date keys off Phoenix's frost dates of Jan 27.
Step 1 · Sow
Direct sow outdoors
Dec 27 – Jan 17
Sow straight into warm, workable soil.
Step 2 · Harvest
Harvest window
Feb 5 – Feb 15
Picking runs until conditions turn against the crop.
Step 3 · Second sowing
Autumn / second sowing
Sep 27 – Oct 11
A second window for a fall crop, timed to mature before the first frost.
Step 4 · Second harvest
Autumn crop harvest
Nov 13 – Nov 23
Maturity window for the second sowing.
Window
Days to maturity
40 – 50 d
Phoenix's 314-day season leaves this much room.
Spinach on Phoenix'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
JAN 27
DEC 7
Common questions
When can I sow spinach outdoors in Phoenix?
Direct-sow around late December (Dec 27–Jan 17) in Phoenix, based on its local frost dates. Confidence 80%.
When will spinach be ready to harvest in Phoenix?
Expect to harvest from around early February (Feb 5–Feb 15) in Phoenix, based on its local frost dates. Confidence 74%.
Can I plant spinach in autumn in Phoenix?
Yes — Phoenix supports a second, autumn sowing of spinach around late September (Sep 27–Oct 11), timed to mature before the first fall frost.
How long is the growing season in Phoenix?
Phoenix has roughly 314 frost-free days, which is enough time to grow spinach to maturity outdoors.
The rule of thumb
Sow spinach 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 Phoenix's frost dates.
Confidence 82/100 · Curated · based on NOAA GHCN-Daily 1991–2020 normal · frost dates are probabilities, not guarantees.