Growing Fennel in Zone 3B

Fennel is a beautiful, aromatic herb with a mild licorice flavor. Both bulb and herb types are worth growing.

Zone 3B has a short growing season — start seeds indoors when possible and use season-extending techniques like cold frames and row covers.

Top Growing Tips

• Direct sow — fennel doesn’t transplant well
• Bulb fennel needs cool weather to form; herb fennel is more heat-tolerant
• Keep consistently moist for best bulb development
• Self-seeds prolifically if allowed to flower
• Attracts swallowtail butterflies — their caterpillars love it

Companion Planting

Good companions: dill (same family, attracts same beneficials)

Avoid planting near: most vegetables — fennel is somewhat allelopathic (inhibits nearby plants). Grow separately.

Harvest Timeline

Bulb: 65-90 days from seed; herb leaves anytime

About Zone 3B

USDA Hardiness Zone 3B has an average last spring frost around May 15 and first fall frost around Sep 15. All planting dates above are calculated from these frost dates. Your specific location may vary — check with your local extension office for the most accurate dates.