Seed-start answer
Start basil seeds indoors around Mar 31
In ZIP 48226, start basil seeds indoors around Mar 31, about 35 days before the May 5 last-frost estimate.
Source: detroit-metro 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 48226, the Detroit frost station, and the May 5 last-frost estimate.
Seed starting schedule
Basil dates for Detroit, MI
| Step | Date | How to use it |
|---|---|---|
| Start Indoors | March 31, 2026 | Start seeds under lights or in a bright indoor seed-starting space. |
| Transplant Outdoors | May 15, 2026 | Move hardened-off seedlings outside after the frost-risk window. |
| Direct Sow | May 15, 2026 | Sow seed outside when the crop and soil can handle the window. |