When to plant Rosemary in Zone 5a
In Zone 5a, Rosemary: start seeds indoors around Feb 24–Mar 10; transplant outdoors around May 19–Jun 2. Expect to harvest around Aug 17–Aug 31.
| Step | When |
|---|---|
| Start seeds indoors | Feb 24 – Mar 10 |
| Transplant outdoors | May 19 – Jun 2 |
| Harvest | Aug 17 – Aug 31 |
Tip: Slow from seed and frost-tender in cold zones — most gardeners start from a plant and overwinter indoors.
Zone 5a averages a last spring frost around May 5 and a first fall frost around Oct 1. These are zone averages — look up your ZIP for your exact area.
See the full Zone 5a calendar in the tool →