Arizona · zones 5b–10a
When to plant spinach in Arizona.
Sow between Jan 1 to Jan 26 in a typical year, keyed to Arizona's median last frost around Feb 5. A second, fall sowing fits Sep 1 to Oct 20. Dates below are state medians; your ZIP code shifts them by days to weeks.
The 2026 windows
Spinach dates for a typical Arizona season.
Direct sow
Jan 1 to Jan 26
Keyed to the ~Feb 5 last frost. Sow 0.5" deep, 3" apart.
Fall round
Sep 1 to Oct 20
Counted back from the ~Nov 15 first frost.
Harvest
~42 days later
~0.25 lb per plant over ~1 weeks.
Arizona spans more than one climate: Zone 9 is the most common zone, but the state runs 5b to 10a. That's why the planner works from your ZIP code's frost dates, not your zone — mountain and coastal gardens in the same state can be three weeks apart.