When to plant Dahlia in Zone 12b
In Zone 12b, Dahlia: start seeds indoors around Dec 4–Dec 18; transplant outdoors around Jan 8–Jan 15. Expect to harvest around Apr 18–Apr 25.
| Step | When |
|---|---|
| Start seeds indoors | Dec 4 – Dec 18 |
| Transplant outdoors | Jan 8 – Jan 15 |
| Harvest | Apr 18 – Apr 25 |
Tip: Plant tubers after frost. In cold zones, lift and store them indoors over winter.
Zone 12b averages a last spring frost around Jan 1 and a first fall frost around Dec 31. These are zone averages — look up your ZIP for your exact area.
See the full Zone 12b calendar in the tool →