When to plant Onion in Zone 6a
In Zone 6a, Onion: start seeds indoors around Feb 10–Feb 24; transplant outdoors around Mar 24–Apr 7. Expect to harvest around Jul 2–Jul 16.
| Step | When |
|---|---|
| Start seeds indoors | Feb 10 – Feb 24 |
| Transplant outdoors | Mar 24 – Apr 7 |
| Harvest | Jul 2 – Jul 16 |
Tip: Day-length sensitive — match the variety (long/short day) to your latitude for big bulbs.
Zone 6a averages a last spring frost around Apr 21 and a first fall frost around Oct 17. These are zone averages — look up your ZIP for your exact area.
See the full Zone 6a calendar in the tool →