Easily grown in moist, organically rich, well-drained soils in full sun. May be grown from seed that is sown directly in the garden in spring. Freely self-seeds in the garden. Remove spent flowering stems before seed is produced to avoid any unwanted self-seeding.
Foeniculum vulgare (common fennel) is an upright, branching perennial that is typically grown in vegetable and herb gardens for its anise-flavored foliage and seeds, both of which are commonly harvested for use in cooking. It somewhat resembles a very large dill plant. It grows to 3-5’ (less frequently to 6’) tall and features feathery, compound, aromatic, yellow-green leaves with needle-like segments and tiny yellow flowers in large, flattened, compound umbels. Flowers bloom in mid- to late summer, and are followed by aromatic seeds. Plants have escaped gardens and naturalized in many parts of North America. Flowers are very attractive to butterflies. Fennel is a larval plant for certain swallowtail butterflies.
No serious insect or disease problems. Stem and root rot may occur, especially in poorly-drained soils. Watch for aphids and slugs. Larvae (caterpillars) of swallowtail butterflies may chew on the foliage.
Borders, vegetable gardens, herb gardens, cottage gardens or meadows. Good plant for a butterfly garden. Seeds are commonly harvested for use as flavoring in a variety of foods such as bakery products or sausages. Chopped leaves may be used as flavoring for salads, potatoes or fish.