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. Radish tolerates light frost, so you can sow ahead of the last-frost date and keep harvesting into the cooler fall. There's also room for a fall succession sowing around Sep 20 for a second harvest before frost.
Common questions
How long does radish take to grow in zone 6a?
Radish matures in about 22–30 days from sowing. In zone 6a that means sowing around Mar 25 and first picking around Apr 16.
Will radish survive frost in zone 6a?
Yes — radish tolerates light frost. In zone 6a you can sow 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 radish in zone 6a?
Yes — in zone 6a there's time for a fall sowing around Sep 20 for a second harvest before frost.
For soil, spacing, pests and companion planting, see the full radish growing guide →