GrowZone

Seed-start answer

Start tomatoes seeds indoors around Mar 9

In ZIP 02108, start tomatoes seeds indoors around Mar 9, about 42 days before the Apr 20 last-frost estimate.

Source: boston-logan frost station, USDA zone 7a, 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 02108, the Boston frost station, and the Apr 20 last-frost estimate.

Seed starting schedule

Tomatoes dates for Boston, MA

StepDateHow to use it
Start IndoorsMarch 9, 2026Start seeds under lights or in a bright indoor seed-starting space.
Transplant OutdoorsApril 27, 2026Move hardened-off seedlings outside after the frost-risk window.