When to plant Onion in Zone 2b
In Zone 2b, Onion: start seeds indoors around Mar 21–Apr 4; transplant outdoors around May 2–May 16. Expect to harvest around Aug 10–Aug 24.
| Step | When |
|---|---|
| Start seeds indoors | Mar 21 – Apr 4 |
| Transplant outdoors | May 2 – May 16 |
| Harvest | Aug 10 – Aug 24 |
Tip: Day-length sensitive — match the variety (long/short day) to your latitude for big bulbs.
Zone 2b averages a last spring frost around May 30 and a first fall frost around Sep 1. These are zone averages — look up your ZIP for your exact area.
See the full Zone 2b calendar in the tool →