JANE POWERSpresemts a who's who of garden culprits
IT IS THE time of the year when people who have never grown anything before take to the garden. This is entirely a good thing, and should be encouraged. Growing plants – as every gardener knows – fosters contentment and connectedness with nature, gets one out of the house, makes things look better around the place (usually), produces stuff that one can eat, and provides moderate exercise (we won’t dwell on the pesky business of gardener’s back here). Yet sometimes, when I meet hopeful new gardeners, I feel anxious. Gardening is as full of disappointments as it is of triumphs, and if the first outnumber the second, then the fledgling gardener often fails to get wafted away by the excitement of the process, and loses heart.
The most common nasty surprise is when seedlings or newly purchased plants are involved in disturbing overnight happenings. One day there is a lively line of baby lettuces, and, nearby, a plump and perfect hosta. But, the following morning, the lettuces are nowhere to be seen, and the hosta has been the victim of a shotgun attack. We’ve all witnessed such crimes in our gardens, and have felt baffled, outraged and cheated. Experienced gardeners reading this recognised the likely culprits as soon as they saw the words “lettuces” and “hosta”. But the new gardener may take a while to learn that the perpetrators of the attack were slugs or snails.
This slimy, leaf-munching crew are collectively the number one pest of gardens, according to the Royal Horticultural Society in Britain. The society’s advisory service receives more inquiries related to these creatures than to any other pest. I don’t have figures for Ireland, but we have a more mollusc-friendly climate, so I am confident that they are the chief perps here also.
There are more ways of tricking, trapping, thwarting and killing the offending gastropods than all other garden pests. Although it’s usually my last option, the easiest method of dispatch is poison. The most readily-available blue pellets are based on methiocarb or metaldehyde, which can harm species other than the targeted miscreants. A newer pellet, containing iron phosphate, and sold as Ferramol, is safe for other garden inhabitants, including birds and pets (available from Ecoshop in Greystones, www.ecoshop.ie; and Fruithill Farm in Bantry, www.fruithillfarm.com).
Vulnerable plants may also be protected with collars cut from plastic drinks bottles, or surrounded by barriers of copper, wood ash, baked and crushed egg shells, or dried grass clippings – with varying rates of success. Or the slippery hordes may be encouraged to gather in congenial places (and then disposed of): under strategically placed slates, melon rinds, or empty grapefruit halves. They can also be hunted at night, with headlamp and sharp scissors – which makes squeamish gardeners squirm, but it’s kinder and quicker than poison, and a salutary reminder of how we got to our chosen place in the hierarchy of creatures on this earth.
Slugs and snails may be lured into beer traps for the final, rip-roaring party of their life, or (in the case of slugs and some small snails only) exposed to parasitic nematodes (from Mr Middleton in Mary Street, Dublin, www.mrmiddleton.com; and Fruithill Farm).
The above techniques, carried out obsessively and diligently, will rid the garden of gastropodal felons, or at least keep them at a respectful distance.
But what a lot of work, and what a lot of stress. I mean, the aforementioned information is invaluable, but need not be acted upon immediately. The longer I garden, the more I realise that the single-minded, clobber-and-conquer approach is neither effective nor enjoyable. For a start, a war against all slugs and snails will inevitably result in the slaughter of innocents.
Take the huge and highly visible black slug (Arion ater) – which may also be brown, rust or a kind of greenish-khaki colour. Although it looks like a dangerous glutton, its diet is mainly rotting matter. It may nibble your lettuces and hostas if it happens to be passing, but it’s more likely to hang out around the compost area, helping to process debris, and minding its own blobby business. The slugs that do more damage to plants are, in fact, smaller and more difficult to spot: the garden slug (Arion hortensis), the grey field slug (Deroceras reticulatum) and the keeled slug (Tandonia and Milax sp.).
There are plenty of other unfairly maligned garden creatures, sometimes because their appearance does not fit human ideas of beauty: woodlice, for instance. In the main, the woodlouse – dressed in grey armour and equipped with an alarming number of legs – is a harmless individual, trundling quietly about, and never far from a dark, moist refuge. It is a land-dwelling crustacean, which makes it related to the lobster (a piece of trivia that I’m thrilled to offer). All woodlice are detritivores, eating, as the word suggests, detritus. Occasionally they opportunistically feed on seedlings in a greenhouse, or take a turn at the hole made in fruit (strawberries, for example) by another animal. Apart from these unfortunate propensities, the woodlouse can be considered an ally.
Wasps, because they sting, and because they may blemish ripe fruit, are also detested by some gardeners. Yet, wasps, besides being sweet tooths, are carnivores. The developing larvae live on a diet of small insects (mainly aphids) and caterpillars, which the adults collect from plants. Earwigs are likewise loathed, but again with little justification. Even though they may graze on chrysanthemums and dahlias, they are useful predators, eating quantities of aphids, as well as insect larvae and eggs.
In other words, sometimes is it not clear-cut whether a garden inhabitant is a friend or a foe. Nature did not design things for our species to be at the centre of the universe. Although it may come as a shock, our needs and desires are not part of the big plan.
Therefore, my most urgent piece of advice to new gardeners is to lie low for a bit, gather intelligence, and work out how to maintain balance in your patch. If you provide many different habitats and plant types (trees, shrubs, perennials, annuals, grass), you will attract more living beings, from invisible soil bacteria to the more obviously appealing birds. Such an environment is more self-regulating, as the individuals higher up on the food chain consume those on the links below. Steer clear of poisons, if possible. They will wipe out the plant-eating aphids and whitefly, but they may also kill the tiny carnivores that prey on them. Spiders, ladybirds, hoverflies, lacewings and ground beetles take a long time to rebuild their numbers, and in the meantime the faster-recovering aphid population is having an extended public holiday.
Protect susceptible plants with barriers, and vigilance (those first lettuces are all-important), but do also aim for as biodiverse a garden as possible. If you’re a control freak and find all this too much of a non-human free-for-all, just think of it as delegating the dirty work. jpowers@irishtimes.com
DIARY DATE
Saturday, April 25th, 3.30-5.30pm:Maynooth Flower and Garden Club spring show at Loftus Hall, St Patrick's College, Maynooth. Admission: €4; plant sales and raffle.