Why these dates work in zone 5b
Zone 5b's last spring frost averages May 15 and first fall frost Sep 30 — about 138 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 Aug 19 for a second harvest before frost.
Common questions
How long does radish take to grow in zone 5b?
Radish matures in about 22–30 days from sowing. In zone 5b that means sowing around Apr 17 and first picking around May 9.
Will radish survive frost in zone 5b?
Yes — radish tolerates light frost. In zone 5b you can sow a little before the last frost (around May 15) and keep harvesting past the first fall frost (around Sep 30).
Can I plant a second crop of radish in zone 5b?
Yes — in zone 5b there's time for a fall sowing around Aug 19 for a second harvest before frost.
For soil, spacing, pests and companion planting, see the full radish growing guide →