GrowZone

Seed-start answer

Radishes is usually direct-sown around Feb 20

In ZIP 98101, radishes is usually direct-sown around Feb 20 instead of started indoors.

Source: seattle-tacoma frost station, USDA zone 9a, 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 98101, the Seattle frost station, and the Mar 20 last-frost estimate.

Seed starting schedule

Radishes dates for Seattle, WA

StepDateHow to use it
Direct SowFebruary 20, 2026Sow seed outside when the crop and soil can handle the window.