When to Plant Tomatoes from Your Local Frost Date

Quick answer

Start tomato seed indoors about 6–8 weeks before the selected last spring freeze date. Transplant roughly 1–3 weeks after that reference, once frost risk, cold soil, and chilly nights are no longer working against the plant. The planting calendar turns those offsets into local ranges.

Planting methods

Tomatoes are normally started indoors or purchased as transplants. Harden seedlings gradually before moving them outside. Direct sowing is possible only where the warm season is long enough, so it is not presented as the default national method.

Spacing, depth, and maturity

Sow seed about 1/4 inch deep. Common garden spacing is 24–36 inches, with more room for vigorous unsupported plants. Many varieties mature 60–100 days after transplanting; use the packet value for the selected cultivar.

Worked local-calendar example

If a local 50% last spring freeze reference is April 19, the general indoor window is about late February through early March. A transplant range begins roughly in late April and extends into early May. This is an example calculation, not a fixed date for every ZIP.

Common mistakes

• Transplanting by the calendar while soil and nights remain cold.
• Counting maturity from sowing when the variety lists days from transplant.
• Crowding indeterminate plants without accounting for support and airflow.

Limitations

Freeze normals are not forecasts. Variety, soil temperature, hardening, shelter, heat, and disease pressure can shift the practical window. Check current conditions before planting.