GrowZone

Seed-start answer

Start tomatoes seeds indoors around Mar 19

In ZIP 43215, start tomatoes seeds indoors around Mar 19, about 42 days before the Apr 30 last-frost estimate.

Source: columbus-port-columbus frost station, USDA zone 6b, last updated 2026-06-28. Verify locally before planting high-value crops because microclimates, current weather, and yard exposure can move the safe date.

This uses ZIP 43215, the Columbus frost station, and the Apr 30 last-frost estimate.

Seed starting schedule

Tomatoes dates for Columbus, OH

StepDateHow to use it
Start IndoorsMarch 19, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsMay 7, 2026Move hardened-off seedlings outside after the frost-risk window.