Zone 6a covers 28 days of last-frost dates. We measured Omaha, NE at Apr 14 and Flagstaff, AZ at May 12. 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 6a
Zone 6a's last spring frost averages Apr 22 and first fall frost Nov 1 — about 193 frost-free days. Celery tolerates light frost, so you can set plants out ahead of the last-frost date and keep harvesting into the cooler fall. Starting seeds indoors 10 weeks ahead gives strong transplants ready the moment the soil warms. There's also room for a fall succession sowing around Jul 19 for a second harvest before frost.
Common questions
How long does celery take to grow in zone 6a?
Celery matures in about 100–120 days from transplanting. In zone 6a that means setting plants out around Apr 8 and first picking around Jul 17.
Will celery survive frost in zone 6a?
Yes — celery tolerates light frost. In zone 6a you can set plants out a little before the last frost (around Apr 22) and keep harvesting past the first fall frost (around Nov 1).
Can I plant a second crop of celery in zone 6a?
Yes — in zone 6a there's time for a fall sowing around Jul 19 for a second harvest before frost.
For soil, spacing, pests and companion planting, see the full celery growing guide →