GrowZone

Seed-start answer

Start tomatoes seeds indoors around Jan 4

This uses ZIP 95113, the San Jose frost station, and the Feb 15 last-frost estimate.

Seed starting schedule

Tomatoes dates for San Jose, CA

StepDateHow to use it
Start IndoorsJanuary 4, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsFebruary 22, 2026Move hardened-off seedlings outside after the frost-risk window.