Foeniculum vulgare var. azoricum Seeds | Florence Fennel
LATIN NAME: Foeniculum vulgare var. Azoricum
COMMON NAME: Florence Fennel
Plant Profile
Florence fennel is the one form of the species grown for a vegetable, and the part we eat is not a root and not a true bulb but a packed cluster of swollen leaf bases that fatten at the stem just above the soil. A carrot or a turnip stores food underground; finocchio stores it in the sheathing bases of its own leaves, which is why the bulb sits at the neck of the plant rather than below it.
Above the bulb the plant makes the ordinary tripinnate, thread-fine fennel leaf, blue-green and anise-scented, and in its second year it would throw the yellow umbel like any other fennel. Most gardeners cut the bulb and eat it long before the flower appears, treating the plant as an annual vegetable.
The oil is most concentrated just under the bulb skin and in the leaf, and the level climbs as the plant matures, so a young, tennis-ball-sized bulb tastes softer than an old, softball-sized one. Cutting at the right size is the cook’s main lever for sweetness, and the plant signals readiness by the roundness of the base.
The vegetable type was fixed in southern Italy, and the cultivars there are picked for a fat, short bulb that holds together in the pan rather than for leaf or seed. A whole braised bulb with a squeeze of orange is the dish that travels best, because the anise softens to something almost fruity under heat.
Science & Biotechnology
Each leaf wraps the short stem with a broad, pale base, and in Florence fennel those bases overlap and swell until they form a rounded, crisp, white-green ball. The bulb is mostly water and cell-wall fibre, which gives the crunch, and the anise volatile sits in the same resin canals that run through the foliage above.
Uses & Benefits
The bulb carries trans-anethole and a little estragole, but at a much lower level than the seed, so the flavour is mild and sweet rather than the sharp liqueur note of seed fennel. That gentleness is what lets finocchio be eaten raw, shaved thin into a salad, where a stronger fennel would overwhelm the dish.
In the Italian kitchen finocchio is halved and grilled until the cut face caramelises, braised with olive oil and a little stock, or eaten raw with salt and lemon as a winter salad. The bulb pairs with fish and with pork, and the fronds on top are snipped over the plate as a herb.
Growing from Seed
Florence fennel needs warmth to swell a good bulb, so sow into warm soil after the chill has gone and keep the bed moist so the plants never check, because a check is what tips them into flowering instead of bulbing. It is the most demanding of the fennels, and the one that punishes a cold start hardest.
A second sowing a few weeks after the first stretches the harvest, because each plant makes one bulb and then runs to flower, so a staggered row gives bulbs over a longer window. In a short season the trick is to keep a fresh, young block coming rather than one big planting that matures all at once and then bolts together.
Sow in warm soil and thin the stand by height, keeping the strongest seedlings at about twenty-five centimetres apart once they stand ten centimetres tall, and never crowd them or the bulbs stay small. Work by plant height rather than by a fixed number of weeks, because temperature, not the calendar, drives bulbing.
When the bulb is walnut-sized, draw soil up around the base or wrap it loosely in paper to blanch the lower part pale and shield it from sun scald, which keeps the flesh sweet and tender. Ease the soil back before harvest so the bulb stays clean, and cut it at the neck with a knife when it feels firm.
Our Take
Florence fennel rewards a warm bed and a watchful eye, and I pull the bulbs young for raw salads and leave the big ones for the grill. It grows happily beside Celery seed Apium graveolens and Dill Anethum graveolens, with Parsley seed and Cilantro Coriandrum sativum as border herbs.
Related Reading
Gardeners who grow Florence Fennel often pair it with these related subjects: