Ladybirds are a gardener's friend

URBAN FARMER: The ladybirds charm while the aphids irritate, and the gardeners have a battle on their hands controlling pests…

URBAN FARMER:The ladybirds charm while the aphids irritate, and the gardeners have a battle on their hands controlling pests, writes FIONNUALA FALLON

THERE’S A loveliness of ladybirds in the OPW’s walled garden at the moment. Yes, that’s right, a “loveliness” of ladybirds, because it turns out that these smartly spotted, polka-dotted beetles (just like schools of dolphins, swarms of flies, gaggles of geese or herds of elephants) have their very own collective noun. Who would have thought?

Aphids, on the other hand, don’t (or at least not that I could discover), which is a strange grammatical oversight when you consider that (a) even aardvarks do (it’s called an armory) and (b) the appalling speed with which these sap-sucking little monsters multiply. How often will the average person ever need to refer to an armory of aardvarks? But aphids, as any seasoned urban farmer will already know from bitter experience, are a different matter altogether.

For inevitably it seems that one day your garden or crop is aphid-free, and the next . . . Well, it’s like the whole extended aphid family are suddenly there, all 20 or 30 generations of them. They’re nestled in feeding clusters along the young tomato plants or sucking contentedly on the sap of your newly planted broad beans, like a bundle of newborn babies.

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So what to call them? An annoyance of aphids, perhaps, or maybe a grumble of greenfly?

I’m not sure, but I do know of a man who does. His name is James Lipton and his book, An Exaltation of Larks, which was first published in 1968, is still considered a classic on the subject of “nouns of multitude”. Here, it seems, is a man who knows his “bellyful of bores” from his “murder of crows”.

The loveliness of ladybirds in the walled garden would disagree with any such disparaging terms, because aphids (preferably lots of them) are a very welcome source of food for both the adult ladybird and its larvae. Ants are also big fans, to the point where they “farm” the aphids for the sticky honeydew that they excrete. Keen rivals of the ladybird, they’ll even attack the adults if given the chance. In the OPW’s walled garden, however, the ladybirds (for the moment, at least) have the aphids all to themselves.

“We noticed lots of them on the strawberry plants a few weeks ago, when the weather got milder,” explains OPW gardener Meeda Downey. “They’re eating the whitefly, which is great – it’s always nice to see ladybirds at work in the garden.”

But even with the welcome help of the ladybirds, the OPW gardeners still have a battle on their hands to control garden pests, most of which see the walled kitchen garden as the equivalent of a Michelin-starred restaurant. Already Meeda and colleague Brian Quinn have started taking preventative measures, such as spreading Bionet (available from fruithillfarm.com) on the bed where the carrot seedlings are emerging, to stop the crop being attacked by carrot fly. The newly planted brassicas, including cabbage, cauliflowers, Brussels sprouts and calabrese, are also being covered with garden netting as soon as they go into the ground.

“It’s to stop the bloody pigeons,” explains Brian. “We got away with not netting them the first year but the pigeons know we’re here now. They’ll destroy the young plants if we don’t stop them.”

Aside from pigeons, carrot fly and aphids, there are also plenty of other garden pests waiting in the wings, which is why the gardeners have enrolled the help of SuperNemos (nemo.ie). Invented and developed by Ciaran Walsh and Dr Abdul Al-Amidi with the help of Enterprise Ireland, SuperNemos is an Irish-made biological control that kills not just one but a wide range of damaging, soil-based insect pests (wireworms, cutworms, vine weevils, strawberry root weevils and many more) through the use of microscopic beneficial nematodes that are normally found in healthy soil.

Environmentally friendly and harmless to wildlife, earthworms, bees, bumble bees, pets and children, the product has already been hailed by the Epoch Times as “the future of eco-friendly insect control”. SuperNemos has also been trialled very successfully in some of Ireland’s top nurseries, and should be of huge help to the OPW gardeners.

“We had a visit from Ciaran last week to explain exactly how it works and how best to apply it. He also measured up the garden to see how much we’re going to need and so we hope to start using it within the next few weeks,” explains Brian. “The timing does need to be right, in terms of things like soil temperature and avoiding direct sunlight.”

But what about the ladybirds? “It won’t harm the adult ladybirds at all and it would only harm the larvae if we were spraying it on to the leaves using a wetting agent to make it stick.”

Dr Al-Amidi confirms that this is the case, adding that the ladybird larvae also need a constant temperature of between 15 to 20 degrees before they begin to hatch, something which we haven’t had so far this spring. So are the gardeners hopeful that this is the answer to their prayers? “If it works as well as we hope it will, then absolutely,” grins Meeda. “It’ll save us a lot of time.”

Time is what the OPW gardeners need right now, as they race to get hundreds of glasshouse-raised plants into the ground. The brassica plants (sown in the glasshouse in early April) have now been planted outdoors into their own separate beds, as part of the strict crop rotation system that Meeda and Brian practice. Spring onions (White Lisbon and Ramrod) have also been sown in situ elsewhere in the garden, despite the gardeners’ worries about the reappearance of the damaging fungus, white rot, which did such damage last year.

“We’re keeping our fingers crossed and praying for a dry summer,” says Meeda with some trepidation. She sowed the seed two to three centimetres apart into weed-free and well-raked soil, and in long parallel drills that are just 10-15cm apart.

“There were something like 10,000 seeds in the packet and we used the lot up, so we should have loads of plants. They should be ready to harvest in about two months time, but we’ll also sow again in two to three weeks time, to keep a constant supply available for the café next door – they always use lots of spring onions.”

Lots of spring onions? Loads of spring onions? I’m not sure if those are the kinds of collective nouns that Lipton would strictly approve of. How about a stash of spring onions instead? Perhaps a squad? Or a slew? Hmm. On second thoughts, perhaps “lots” or “loads” is just fine.

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. Open daily from 10am to 4.30pm

Next week: growing asparagus

Fionnuala Fallon is a garden designer and writer

WHAT TO: Sow, plant and do now

Sow under cover with heat (minimum 20ºC):tomatoes; aubergines; peppers; celeriac; cucumbers; pumpkins; sweet corn; sunflowers; courgettes.

Sow under cover: Brussels sprouts; hybrid broccolis; dwarf, French and runner beans; kohl rabi; mini, summer and autumn cauliflowers; endive; calabrese; summer and autumn cabbage; cut-and-come-again crops; celery; leeks; lettuce; Swiss chard; lettuce.

Sow outdoors: broad beans; beetroot (early, bolt-resistant variety); autumn and winter cabbage; calabrese; carrots; parsnip; summer and autumn cauliflowers; peas; mangetout; sugar snap; radish; rocket; spinach (annual and perpetual); swedes; turnips.

Plant: onion and shallot sets; lettuce; maincrop potatoes; asparagus (module-raised).

Do:weed and dig beds; prepare seedbeds; continue sowing seed and pricking out seedlings; organise seed/seedling swaps; harden off well-established plants; finish planning crop rotations.