When to Plant Rosemary
A Mediterranean herb that can become a beautiful evergreen shrub in mild climates. Incredibly aromatic and drought-tolerant.
The Short Answer
How to Grow Rosemary
Rosemary is a Mediterranean evergreen shrub that becomes a permanent fixture in mild-winter gardens (zones 7+) and a potted herb that overwinters indoors in cold zones. It's the most drought-tolerant culinary herb and the most resentful of overwatering — root rot from wet feet kills more rosemary than cold ever does. In-ground plants can reach 4 feet tall and wide in warm climates. Arp and Hill Hardy are the most cold-tolerant varieties. Woody stems don't produce new growth, so prune only into green wood and never more than one-third of the plant.
Starting Seeds Indoors
Begin rosemary seeds indoors 12 weeks before your average last frost date. Seeds need soil temperatures of at least 65°F to germinate, which typically takes 14-21 days. Provide 14 hours of light per day using a south-facing window or grow lights.
Transplanting
Move seedlings outside 2 weeks after your last frost date, once soil temperatures reach 65°F. Harden off seedlings for 10 days before transplanting by gradually exposing them to outdoor conditions.
Growing Tips
Buy transplants rather than growing from seed — germination is slow and unreliable. Overwinter indoors in zones 6 and colder.
Companion Planting
Good companions:
Rosemary Planting Dates by State
Click your state for rosemary planting dates specific to your location:
Last reviewed: March 29, 2026