In the Garden
Fern-like fennel forms a lush clump of foliage.Plant fennel in your herb garden, vegetable garden, flower bed, and especially your butterfly garden, where it is food for black swallowtail caterpillars. The plants, which sport shiny, hollow green stems and fern-like foliage akin to that of dill, grow to an average height of 3 to 5 feet when in full bloom. The plant stays green through the winter in Zone 8 and farther south and bears umbels of yellow flowers in the summer. While perennial through Zone 7, it is generally grown as an annual farther north.
Planting and Care
The umbels of fennel flowers are a beautiful example of nature's design.Set out your Bonnie transplants after the last spring frost, in rich, well-drained soil with a pH between 4.8 and 8.2. Choose a sunny spot and add a slow-release fertilizer to the soil before or while planting.
To encourage new leafy growth, pinch flower heads as they appear. If your plant looks straggly or unkempt, cut it back to about a foot above the ground to get new growth. Despite its quick growth and impressive height, fennel doesn’t usually need staking unless your area is prone to heavy summer rains or winds. After mid-summer you can let the plants bloom and produce seed if you wish to harvest the seed, or let it drop to the ground to self-seed the planting for next season.
Troubleshooting
The pretty caterpillar of a black swallowtail butterfly is a welcome guest on fennel in most gardens.Avoid planting near dill if you want either plant to reseed, because dill and fennel can cross-pollinate, resulting in a next generation of off-flavored plants. Cilantro, known to reduce fennel’s seed production, should also be kept separate.
Watch for aphids, which can ruin the fine foliage quickly. The parsleyworm likes fennel, too, but this caterpillar turns into the beautiful black swallowtail butterfly. Manage this by simply planting extra fennel for them to enjoy.
Harvest and Storage
Harvest foliage, stems, and flowers at any time throughout the growing season, cutting as you need them. The plant is slightly frost tolerant, so you can harvest through the onset of cool weather. The foliage can be frozen in water or dried.
To harvest the seeds, wait until they are brown, but get them before they drop from the plant. Collect them by cutting the seed heads and a bit of the stalk; then, in a warm, dry area, hang them upside-down in a paper bag. Once the seeds have fallen into the bag, store them in an airtight container.
Uses
Use the mildly licorice-flavored foliage for soup and salad garnish or bundled into bouquet garni for fish. Stems and flowers are nice in salad or as a garnish, and small sections of the yellow flower cluster may even be eaten as after-dinner mints. Chopped fennel leaves are also excellent in other seafood dishes, tomato and bean dishes, with vegetables, and in mayonnaise, vinaigrette dressings, or herbed butters. The big stems can be grilled with fish or meats.
Crush the sweet seeds lightly to release their flavor. These are good in cabbage, pork or sausage, and Italian dishes including pizza.
Vinegar or oils infused with fennel are great in sauces, marinades, and salad dressings, too.