Growing Bulb Fennel

Benedict Vanheems
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For those in the Northern Hemisphere the longest day of the year falls on either the 20th or 21st June (for Southern Hemispherists it’s the 21st/22nd December). The longest day of the year marks a distinct turning point in the gardener’s calendar, with summer well and truly in command and, hopefully, the first flush of harvests coming and thick and fast if not already snaffled up.

With the likes of early peas and potatoes, broad beans and carrots lifted and plucked, the first free gaps on the plot will be making an appearance round about now. Of course, no vegetable grower worth his salt needs reminding that this is the perfect signal to sow and plant once more, for crops that will be enjoyed in a few months’ time and on into autumn/fall. For me, spring is very much a mad rush to get everything up and running before the really good growing weather arrives; starting off veg from midsummer is a more relaxed affair – a far cry from the sprinter’s pace of those earlier sowings.
Fabulous Florence fennel

Perhaps the most indulgent vegetable to start off at this time of year is Florence fennel, otherwise known as finocchio or, more commonly, bulb fennel. The handsome feathery foliage of this crop is matched only by its exquisite aniseed flavour that makes a fine pairing with fish (try baking parcels of mackerel with slices of fennel and lemon for a sublime dinner). But fennel has more strings to its bow than this – pop chunks into a stew to freshen things up, or finely slice a bulb over a garden-gathered salad using a chef’s mandolin. The leaves can be used in place of herb fennel.

Bulb fennel is perhaps a slightly misleading name, as the ‘bulb’ is in fact the swollen stem base of the plant. But this is nitpicking as all you really need to know is that this is a vegetable to luxuriate in – a gourmet kitchen gardener’s treat!
The right site

One of the reasons to sow bulb fennel at midsummer is its love of sunny conditions. Hailing from the Mediterranean, it is at home in a fertile yet free-drained soil that’s lovingly basked by the warming rays of summer. While those in Mediterranean-equivalent zones can of course sow in spring, those at more northerly latitudes must bide their time to be sure of success. By midsummer the soil will have warmed up more than adequately and success will be all but assured.

Despite its sun-kissed origins, however, bulb fennel will not tolerate dry conditions. While a moisture-starved soil isn’t necessarily bad for the plant itself, it’s not great news for us; dry soil encourages plants to run to flower prematurely at the expense of those juicy bulbs. Soil that was manured for a previous crop and that’s topped with a mulch of organic matter will stand a better chance at retaining that all-important soil moisture.

To be sure of adequate moisture it is likely you’ll need to thoroughly water the ground before re-sowing with fennel. Beware the thick canopies of the potato, which exclude all but the heaviest downpours of rain. Having lifted all of your spuds the soil that’s left has a tendency to be dust-dry. Either wait for a good rainstorm to pass before sowing your fennel, or go over the ground several times with the watering can or hose to re-wet. Bulb fennel can also be grown in containers of multipurpose compost.
Sowing and growing

Sowing is easy and best done direct where the bulb fennel is to grow. Sow the seeds into weed-free soil that’s been raked to a fine texture, setting seeds about 1cm (0.5in) deep. You can either station sow three or four seeds every 25-30cm (10-12in) each way, thinning to leave the strongest seedling at each position, or sow the seeds in rows before thinning in stages. It’s also possible to sow into module trays of compost before planting out, but do this promptly as the plants absolutely hate root disturbance.

Few pests will trouble your seedlings but slugs (as ever!) can be the exception. Nightly patrols to collect the slimy molluscs, the laying of beer traps or a sprinkling of pet-safe slug pellets will help to control the population.

As the stem bases begin to swell plants can be ‘earthed up’ just like potatoes by pushing loose soil up against the bases. This not only produces paler and hence more tender bulbs, it will give plants proper support and keep them from rocking back and forth in the wind.
Bolt out of the blue

Don’t let your bulb fennel run to seed or 'bolt'. The number one rule when growing this otherwise easy-care vegetable is that you must – and I mean must – keep the roots quenched (though never waterlogged). Water during any dry spells and apply a mulch of grass clippings or similar around the plants to lock it in.

Modern varieties are proving ever more resistant to bolting. The roll call of bolt-resistant varieties includes ‘Victoria’ with its orderly foliage, late-season ‘Cantino’ and the appropriately-named ‘Perfection’. Look out for them. In the very hottest climates heat alone can induce flowering – shading from other taller crops or temporary netting can alleviate the heat.

If one or two plants do stretch to flower, don’t despair. There’s no hurry to lift them out for the compost bin. The yellow umbels that follow not only look fantastic but are a powerful draw for all manner of beneficial insects. Fennel in full flower is a stunning sight and you could even put the case that your fennel is acting as pollinator/pest predator provider!
Enjoying the bulbs

Bulb fennel can be used at any size, with the smallest and most tender bulbs best for use raw in salads. Warm bulbs taken during the heat of the day can be freshened up by submerging thin slices in a bowl of iced water for up to an hour. They’ll soon regain their rigidity and full flavour. Cut the bulbs an inch above ground level and allow the stump to re-sprout (a trick that also works for cabbages). The bonus take of feathery shoots is both delicious and delicate.

However you use your bulb fennel you’ll be pleased you made the sowing. Just think, within just two months of reading this you could be enjoying the luxury of your own bulbs. It’s a tempting thought.