Zone 8a covers 26 days of last-frost dates. We measured Little Rock, AR at Mar 9 and Baltimore, MD at Apr 4. Give us your town or ZIP and we'll use ten years of daily lows recorded at your own coordinates instead of the middle of that range.
Why these dates work in zone 8a
Zone 8a's last spring frost averages Mar 15 and first fall frost Nov 19 — about 249 frost-free days. Rosemary is frost-sensitive, so the around last frost timing builds in a safety margin against a late cold snap — setting plants out too early risks losing them to frost. Starting seeds indoors 10 weeks ahead gives strong transplants ready the moment the soil warms.
Common questions
How long does rosemary take to grow in zone 8a?
Rosemary matures in about 80–100 days from transplanting. In zone 8a that means setting plants out around Mar 15 and first picking around Jun 3.
Will rosemary survive frost in zone 8a?
No — rosemary is frost-sensitive. In zone 8a, wait until after the last frost (around Mar 15) to plant, and harvest before the first fall frost (around Nov 19).
For soil, spacing, pests and companion planting, see the full rosemary growing guide →