When to plant Rosemary in Zone 5b
In Zone 5b, Rosemary: start seeds indoors around Feb 19–Mar 5; transplant outdoors around May 14–May 28. Expect to harvest around Aug 12–Aug 26.
| Step | When |
|---|---|
| Start seeds indoors | Feb 19 – Mar 5 |
| Transplant outdoors | May 14 – May 28 |
| Harvest | Aug 12 – Aug 26 |
Tip: Slow from seed and frost-tender in cold zones — most gardeners start from a plant and overwinter indoors.
Zone 5b averages a last spring frost around Apr 30 and a first fall frost around Oct 5. These are zone averages — look up your ZIP for your exact area.
See the full Zone 5b calendar in the tool →