GrowZone

Seed-start answer

Start lettuce seeds indoors around Jan 18

This uses ZIP 85701, the Tucson frost station, and the Feb 15 last-frost estimate.

Seed starting schedule

Lettuce dates for Tucson, AZ

StepDateHow to use it
Start IndoorsJanuary 18, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsFebruary 1, 2026Move hardened-off seedlings outside after the frost-risk window.
Direct SowFebruary 1, 2026Sow seed outside when the crop and soil can handle the window.