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. Broccoli 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 6 weeks ahead gives strong transplants ready the moment the soil warms. There's also room for a fall succession sowing around Jul 1 for a second harvest before frost.
Common questions
How long does broccoli take to grow in zone 5b?
Broccoli matures in about 80–100 days from transplanting. In zone 5b that means setting plants out around Apr 24 and first picking around Jul 13.
Will broccoli survive frost in zone 5b?
Yes — broccoli tolerates light frost. In zone 5b you can set plants out 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 broccoli in zone 5b?
Yes — in zone 5b there's time for a fall sowing around Jul 1 for a second harvest before frost.
For soil, spacing, pests and companion planting, see the full broccoli growing guide →
