When to plant Onion in Zone 8a
In Zone 8a, Onion: start seeds indoors around Jan 11–Jan 25; transplant outdoors around Feb 22–Mar 8. Expect to harvest around Jun 2–Jun 16.
| Step | When |
|---|---|
| Start seeds indoors | Jan 11 – Jan 25 |
| Transplant outdoors | Feb 22 – Mar 8 |
| Harvest | Jun 2 – Jun 16 |
Tip: Day-length sensitive — match the variety (long/short day) to your latitude for big bulbs.
Zone 8a averages a last spring frost around Mar 22 and a first fall frost around Nov 18. These are zone averages — look up your ZIP for your exact area.
See the full Zone 8a calendar in the tool →