URBAN FARMER:The spoils of war from a cutworm infestation at the OPW's walled garden in the Phoenix Park have gone to a cheeky robin

WHOLESOME, RELIABLE and traditional it may be, but even its biggest fans will agree that the common cauliflower is not the most glamorous of vegetables.

Certainly, it’s not one of the aristocrats of the kitchen garden, in the way that the artichoke or the asparagus is, nor does it bring a whiff of exoticism to the kitchen table, as the courgette or the artichoke do. No, the cauliflower is not a vegetable that the urban farmer finds it easy to get excited about. At least not, that is, until you start growing your own and discover that not only is it trickier than it looks, but that it’s also a more varied vegetable than many give it credit for.

How many urban farmers know, for example, that there’s a bright orange form of cauliflower, which first appeared as a natural mutation in Toronto almost 40 years ago? Its cultivar names include Cheddar and Orange Bouquet and it contains 25 times the Vitamin A levels of traditional white varieties of cauliflower. Or that there’s also a purple-violet form (look out for varieties called Graffiti and Purple Cape) as well as a lime-green type with spiky florets known as Romanesco?

The cauliflower’s history, too, is more interesting than one would expect – the Arabs were big fans of the vegetable, which they were growing as far back as the Middle Ages, with the cauliflower first reaching Europe in the 1400s via Spain.

In the OPW’s walled garden in the Phoenix Park, the humble cauliflower also has plenty of fans, although unfortunately not all of them are human. Instead, the crop is being destroyed by a plague of cutworms, which are sawing through the young stems at a rate of knots. “Like nasty little lumberjacks,” says OPW gardener Brian Quinn with undisguised disgust, as he surveys the devastated crop.

This destructive little garden pest is the soil-dwelling larvae or caterpillar of several different varieties of moth (including both the lesser and large yellow underwing, the turnip moth, the heart-and-dart moth and the garden dart). It likes to eat the roots, stem and foliage of many young vegetable plants and seedlings, often systematically working its way along a row or drill.

While Brian has seen signs of it in the walled kitchen garden before, the scale and speed of the damage in the last couple of weeks has taken him and fellow gardener Meeda Downey by surprise. Worse still, he thinks that they might be partially to blame.

“I’m not sure but I’ve an awful feeling that the tobacco plants we’re growing might be part of the problem,” he says. “Nicotiana lets off a strong perfume at night to attract pollinating moths, and I’m worried that it’s maybe doing too good a job and also attracting the parents of the cutworm, which are laying their eggs nearby.”

His theory is given weight by the fact that the cutworm infestation is worse close to the tobacco plants, with almost a third of the nearby cauliflower plants badly affected. The big problem for Meeda and Brian is that control or eradication of this garden pest is extremely difficult.

“Because we’re using organic methods, we obviously don’t use chemical controls, but even if we could, they’re not that effective against cutworms anyway. Last year, we put collars around the base of each plant, which helped to stop the damage but we just never got around to it this year,” says Meeda.

“At the moment, we’re just keeping a really sharp eye out for any damage,” says Brian, adding that in the last week they’ve lost almost a third of their young Lollo Rosso lettuce plants to the pest. “Wherever we see a plant dying, or suddenly falling over, we’ll start digging down around the roots until we find the creamy-brown caterpillars hiding in the soil. The annoying thing is that they stay below ground during the day, when they eat the roots of the plant. It’s only at night-time, when we’re not around, that they come to the surface and feed on the stems and the lower leaves. It makes them really hard to get at.”

Because the cutworm infestation has only really taken hold in the last few weeks (it’s typically at its worst in July and August), it didn’t affect the early summer-cropping cauliflowers, which have already been lifted. But the autumn and winter (spring headed) types, which were sown in late spring and only planted in mid-summer, have been very badly hit.

Large and obvious gaps in the neat drills point to the damage already wreaked, and if Meeda and Brian don’t do something soon, there may be no cauliflowers at all in a couple of weeks. But Brian, as always, has been doing some careful research on how best to foil the walled garden’s latest enemy.

“The cutworm really likes bran, apparently,” he says. “And then there’s a kind of natural biological control, a bacteria called Bacillus Thuringensis, which will kill any caterpillars that feed on it – it paralyses their digestive tract. So the idea is to soak the bran in this biological control and then scatter it around the ground where the cutworm infestation is worst. I’ve also read that soaking bran in iron phosphate (the active ingredient in the organically-approved slug pellets, Ferramol) will kill them too. So we’re hopeful that one or other of these will do the trick, but we’ll just have to wait and see.”

In the meantime, the OPW gardeners have yet another little trick up their sleeve – it’s another natural predator of the cutworm but this time it’s of the feathered variety. A young robin, one of this year’s fledglings, quickly spotted the possibilities that the cutworm offers in terms of adding some variety to his diet. “He seems to have worked out very quickly that Meeda and I are digging the caterpillars up and that it’s a nice, easy way for him to get some tasty food,” says Brian. “At first, he just watched us and then, as he got braver, he came closer and closer. So I held a few of the caterpillars in my hand, to see what he’d do. He’s a really cheeky little fellow – he started landing on my hand to feed, and now he follows me around the garden like an addict. He seems to just love the taste of the caterpillars, even more than ordinary garden worms. In fact, I don’t think he’ll be too pleased if we do actually manage to get rid of them.”

As for the damaged cauliflower crop, it’s too late to sow replacement plants for the autumn and winter (spring-headed) varieties. However, next month the OPW gardeners can sow seed of the early summer types, including varieties such as Mayflower, Montana and Gipsy.

Thompson Morgan also do two varieties, Avalanche and All The Year Round that can either be sown in October and overwintered in a cold frame before planting out for an early summer crop, or sown from February until May the following spring to crop in late summer/early autumn. By which time, Brian and Meeda are bound to have the cutworm problem under control. Much to the disgust, one expects, of one plump and particularly cheeky robin.

** The Waterford Harvest Food Festival will take place from tomorrow till Sunday. Part of the celebrations will include the formal launch on Saturday of GIY (grow it yourself) Ireland by the Minister For Food and Horticulture, Trevor Sargent. Speakers include Michael Kelly, Joy Larkcom and Darina Allen. Cost, including lunch, is €35. To book, visit www.giyireland.com

** The OPW’s Victorian 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 how this year’s wet summer may have affected your fruit and vegetable crops and liming your soil

Fionnuala Fallon is a garden designer and writer