Seed-start answer
Spinach is usually direct-sown around Apr 7
In ZIP 80012, spinach is usually direct-sown around Apr 7 instead of started indoors.
Source: denver-intl frost station, USDA zone 6a, 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 80012, the Denver frost station, and the May 5 last-frost estimate.
Seed starting schedule
Spinach dates for Aurora, CO
| Step | Date | How to use it |
|---|---|---|
| Direct Sow | April 7, 2026 | Sow seed outside when the crop and soil can handle the window. |