What lies beneath: getting to the root of winter veg

URBAN FARMER:It's now that the hearty and healthy qualities of underground root vegetables come into their own, writes FIONNUALA FALLON

“I’M GOING underground” sang the English rock star Paul Weller almost 30 years ago, but I’m pretty sure he wasn’t referring to root vegetables at the time. (The lyrics: “You choose your leaders and you place your trust, and their lies put you down and their promises rust” suggest other concerns). Given the hideous weather and flooding of the last week, most urban farmers couldn’t be blamed for following Weller’s lead, if only to get a little respite from the rain.

But if the winter storms don’t make you feel like retreating, hobbit-like, underground, then grab your garden fork and dig up the ground instead. For it’s exactly now, in these dark days of winter, that the hearty, healthy and nourishing qualities of underground root vegetables like parsnips, carrots, swedes, turnips, salsify and scorzonera really come into their own to earn their spot in the vegetable patch.

Apart from their undoubted usefulness, there’s also something quite magical about going out to the garden at this time of year and digging up what, to the uninitiated, looks like dead leaves or bare soil, only to uncover the buried treasure of a neat line of parsnips or the bright orange of the last of the summer’s carrots.

Unlike many leafy or above-ground crops, the wonderful thing about many winter root vegetables is that they can be left safely in the soil until quite late into the year, undamaged by cold or rain.

In the OPW’s walled organic kitchen garden in the Phoenix Park, gardeners Meeda Downey and Brian Quinn are still harvesting the last of a late-sown crop of beetroot (Chioggia Pink and Egyptian), as well as the knobbly, turnip-like roots of spring-sown celeriac.

“We did have plenty of parsnips as well, but we lifted them early as we wanted to sow a green manure for the winter. Otherwise, they could have been left in the ground, and harvested over the winter months, which improves the flavour. Swedes and turnips are also still fine in the ground until the end of the year, but their taste starts to go off after that,” says Meeda.

Those urban farmers who struggle to produce celeriac of any size (and there are many) will be particularly envious, for Brian and Meeda have grown a fine crop of this tasty winter root vegetable in the walled garden this year. The trick, it seems, is sowing early, under cover and with heat, because celeriac needs a particularly long growing season.

The OPW celeriac (a variety called Prinz) that Meeda and Brian are now harvesting was sown back in February of this year in the nearby heated glasshouses, and was kept under cover for some months before being planted out in May. The OPW gardeners then kept a close eye on the plants throughout the summer months, giving them regular liquid feeds made from the organic granular fertiliser, Osmo, dissolved in water. (Alternatively, other urban farmers could use a liquid feed made from the leaves of comfrey).

Brian and Meeda were also careful to gradually remove the outer ring of leaves as the roots slowly swelled, and to keep the plants well watered during dry spells. The result is three fine rows of celeriac, enough to keep the next-door Phoenix Café supplied right up until the new year.

“We’ve just started harvesting it now, so it’s been a very long time in the ground in comparison to other crops,” says Brian. “But that’s what you need to do if you want celeriac to grow to a decent size – sow it early but don’t plant it out until after the frosts, and then leave it to grow for as long as possible. Next year, we’re going to give the variety Prague Giant a go, as it’s supposed to be a particularly heavy cropper.”

The earthy-flavoured white flesh of this unusual vegetable is delicious when used in soups and salads, or cut into chips and roasted, although special care must be taken to prevent it from discolouring.

Food writer Jane Grigson, who was a big fan of celeriac, recommended dropping the freshly peeled flesh into a bowl of “acidulated” water (one tablespoon of vinegar per litre) or rubbing it with lemon juice. She blamed its tendency to discolour for the vegetable’s otherwise inexplicable lack of popularity, and rated it highly as a convenient and storable form of celery flavouring. Vegetable expert Joy Larkcom also recommends using the strong-tasting winter leaves (sparingly) in salads.

Parsnips are yet another tasty and useful root crop at this time of year, but also another vegetable that requires a long growing season if success is to be guaranteed. Because of previous problems with slow, poor or inconsistent germination (parsnip seed is famed for this), the OPW gardeners sowed their parsnips in the form of seed tape last spring.

“Parsnip seed needs to be station-sown (at regularly spaced intervals, and in clusters) and the tape speeded up what can be a slow process. The regular spacing of the seed on the tape also meant we could judge successful germination more accurately, rather than searching for any young seedlings that might (or might not) have appeared,” says Brian.

Equally, those urban farmers whose parsnips are still in the ground should remember to mark their location now before the foliage dies down and the crop hides itself underground.

Aside from their wholesome flavour, the medicinal and curative properties of parsnips were also once much valued, according to Jane Grigson, who says that “medieval doctors credited parsnips with several virtues. They kept off adders, they cured toothache, they gave men an appetite for women, they reduced swollen testicles, they were eaten for stomach ache and the milk they were boiled in was given against dysentery”.

But those urban farmers who suffer from none of the above complaints can simply enjoy the delicious flavour of this tasty root vegetable, whether buttered, fried, baked, curried or creamed.

Two other similar but lesser-known winter root vegetables are salsify and scorzonera, both vegetables with long, tapering tap roots that are also ready to be harvested around this time of year. Of the two, salsify (also known as the vegetable oyster) is probably the more useful crop, for not only is its finely-flavoured root edible during the winter months but so, too, are its purple flowers and young shoots in springtime.

Scorzonera, although similar in appearance, is considered slightly tastier but is another very slow-maturing root crop that will sometimes need to be left in the ground until the following autumn before being ready to harvest. Just like parsnips, the flavour of both these root vegetables is improved by winter frosts so leave crops in the ground if possible rather than lifting and storing them. And just like celeriac (and parsnips, for that matter), the roots quickly discolour once peeled, so follow Grigson’s advice here also.

The trick to successfully growing any of these winter root vegetables next year is to cultivate the ground now, digging the soil deeply, removing any large stones, incorporating plenty of farmyard manure/compost/leaf mould and liming if necessary. That way, the ground will be in prime condition come next spring, when it’s time to sow seed.

The big problem for most urban farmers will be getting the opportunity to do so, as torrential rains have made most soils unworkable. Even in the OPW’s well-drained walled garden, the downpours of the past few weeks have made the ground temporarily waterlogged, preventing Brian and Meeda from digging or rotovating for the moment. “You’ll do more damage than good if you try to dig very wet soil,” says Brian. “So it’s best to wait until things have dried out a bit.”

In the meantime, if you are one of the urban farmers who grew either salsify or scorzonera this year, then it seems that you belong to quite an exclusive group. After bemoaning the fact that neither vegetable has ever really been popular with the general public, Grigson goes on to say that “intelligent gardeners, from John Evelyn onwards, have always grown either salsify or scorzonera”.

So there you have it. Not only are your root vegetables good for you but some of them are also a measure of your IQ. Who ever would have thought it...

WHAT TO: sow, plant and do now

Sow outside now:broad beans, hardy peas, some green manures (winter field bean, winter rye)

Sow under cover with heat, then grow in unheated tunnel/glasshouse/sunny windowsill:winter salad mixes

Plant outside now:garlic, onions, shallots, rhubarb sets

Do now:clear, dig and manure soils; collect leaves for leafmould; lift and store root crops such as carrots, turnips, swedes, late-sown beetroot; harvest winter, autumn and red cabbage, swiss chard and spinach; protect celeriac, second-crop potatoes from frost; stake any leggy Brussels sprouts; order seed catalogues for next year

The OPW’s walled kitchen garden is in the grounds of the Phoenix Park Visitor Centre, beside the Phoenix Park Café and Ashtown Castle. The gardens are open daily from 10am to 4.30pm

Next week Urban Farmer in Property will cover growing your own Christmas dinner

Fionnuala Fallon is a garden designer and writer