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. Lemon Balm 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.
Common questions
How long does lemon balm take to grow in zone 5b?
Lemon Balm matures in about 60–90 days from transplanting. In zone 5b that means setting plants out around May 15 and first picking around Jul 14.
Will lemon balm survive frost in zone 5b?
Yes — lemon balm 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).
For soil, spacing, pests and companion planting, see the full lemon balm growing guide →
