I could extol the virtues of fennel as a culinary herb but the truth is that I grow it for its stately beauty and rarely clip it for consumption. I like the mild licorice flavor of its leaves, stems, and seeds in salads and bread, but its fine delicate texture is what I admire most, with the large heads of yellow flowers a close second. It adorns my garden from the moment it comes to life in spring with the emergence of its feathery foliage, throughout the summer when it blooms, and looks good into fall as it keeps producing new foliage as I whack it back to make room for late blooming plants. I have both green and bronze varieties and grow them in different borders towards the front of the bed as “see through” plants. As an added attraction, the plants attract black swallowtail butterflies that lay their eggs on the plants so their larvae have a tasty treat as soon as they emerge from the eggs. Yes, they can consume a large amount of leaves but the leaves grow back quickly and the plants are none the worse for the experience. Fennel is very easy to grow and comes back year after year in my North Carolina garden often reseeding. The bad news is that fennel is allelopathic and may cause harm to other plants by inhibiting growth, causing them to bolt, or outright killing them. I have not personally had any problem with using fennel in my flower beds, but be forewarned that they may not be good plant companions.
Type: Perennial herb.
Bloom: Large umbels of small yellow flowers are produced in summer.
Foliage: Finely dissected deep green leaves. Bronze-leaf variety available also.
Size: 4-5’ H x 2-3’ W.
Light: Full sun.
Soil: Organically rich, moist, well drained.
Hardiness: Zones 4-9.
Care: Clip leaves for use once the plant is established and freeze for later use if desired. Harvest seeds when they turn from yellowish-green to brown by clipping the flower heads and placing them in a bag stored in a warm dark place until the seeds are completely ripe, then store in jars. When using leaves in cooking add them at the very end of the cooking time as heat destroys their flavor.
Pests and Diseases: None of significance but plants may be susceptible to root rot in poorly drained soils, aphids, and slugs.
Propagation: Seed (reseeds it self).
Companion plants: Fennel is allelopathic to some garden plants meaning that will inhibit or hurt their growth. Susceptible plants include bush beans, tomatoes, and kohlrabi.
Outstanding Selections: Foeniculum vulgare ‘Purpureum’ (bronze leaves).