Article by Carol Bartlett, of The Sunday Gardener
Slugs are officially the gardener’s No 1 enemy. Turn your back for a gardening moment, and these tough-skinned terrestrial molluscs will completely shred new shoots and tender lettuces.
Given that they have neither mouth parts nor teeth, slugs eat a disproportionate amount by using their surprisingly efficient rasping tongues. Make no bones about it – when it comes to slugs – it’s war! Here are some handy prevention tips to help you beat the slugs.
How to deter slugs – the barrier method
Slugs can cause havoc in the garden, but the good news is that there are a number of really effective deterrents.
Slugs don’t like sliding over rough dry surfaces. This works well where raised beds are constructed from rough sawn wood, such as old railway sleepers. The texture of the timber is not ideal for slugs, and mostly they prefer not to tackle it. My lettuces were untouched last season.
You can also buy adhesive copper tape to circle pots and containers – slugs and snails don’t like to cross the barrier as it gives them a mild static electric shock.
Other barrier methods such as coffee beans and egg shells are often suggested, but I don’t find them particularly effective. They can look unsightly and lots of coffee beans are not ideal for the soil. Wood ash and grit work to some extent, but are not foolproof.
Organic methods to get rid of slugs
Slug Nematodes are an organic method of control. They need to be watered into the ground when the soil has warmed up to at least 5 degrees. Once watered in, the micro-organisms will go to work on the slugs. Generally a repeat application is beneficial 6 weeks later. Nematodes are widely available and repeated use, year on year, will diminish your slug population over time.
Undoubtedly, one of the most effective organic methods of slug control is to place beer traps around your garden and sensitive plants. You can make your own using small containers, but the advantage of bespoke traps is that they have lids. In our climate, keeping a lid on the beer really helps, otherwise it can become too diluted by rainwater to work its magic. Any ‘value’ beer will do the job. Sink the container into the soil so the slug can access it easily. Slugs are attracted to the beery smell, fall in and die. The only downside is that emptying slug traps is not for the faint hearted, it’s a smelly job.
Organic slug pellets are good and safe to use. Non-organic versions, based on metaldehyde, can be dangerous to pets and wildlife. Keep a tub handy to scatter around vulnerable new shoots and plants. Rain does render the pellets ineffective so it’s necessary to reapply frequently.
If you’re not squeamish, you can’t beat “picking and dispatching” as an organic method of reducing the slug population. Slugs are mostly nocturnal and are particularly active after a rain shower. Armed with a pair of tongs and a sharp stick it’s easy to dispose of a dozen or so. Placing an upturned orange or grapefruit will encourage the slugs to collect underneath, which makes them easy to find and dispatch.
Encouraging wildlife into the garden such as frogs and hedgehogs will also help, as they like to snack on slugs. But even a lot of frogs won’t solve the problem – you’ll still need additional protection.
What are the best plants for gardens with slugs?
If you’re really struggling with slugs, opt for plants that they simply aren’t interested in. Whilst the Hosta is a firm slug favourite, they’re not keen on those varieties with thick ribbed or blue coloured leaves such as Big Daddy, Gold Regal, Liberty, Halcyon, and Silvery Slugproof.
There’s also a long list of perennials that slugs display no interest in such as:
If you love to create a splash with summer bedding plants, good varieties to choose are Pelargoniums (also known as Geraniums), Begonias, Fuchsias, Lobelia and Antirrhinums (Snapdragon). Rather than planting your usual variety of slug-magnet Marigolds, try the English Pot Marigold, Calendula, a lovely bright annual that is of little interest to the hungry molluscs.
How to rescue slug-savaged plants
If the worst happens and your garden is attacked by slugs, don’t despair. You can make a rescue bid. Ragged Hosta leaves can be trimmed and you can remove several entire leaves per season. New leaves will grow and replace those you’ve cut away.
Dig up damaged bedding plants and salvage by giving them some TLC in a protected environment. They’ll recover and regrow in around 2-3 weeks, ready to be planted out again with extra protection.
The best way to win the war on slugs and snails is to keep watch over young and vulnerable plants and employ a combination of methods to keep them at bay. You can never completely eradicate slugs and snails, but over a period of time, you can reduce their numbers and control them.
About the author:
Carol Bartlett, The Sunday Gardener, lives in the north of England where she has created a diverse garden including wildflowers, natural areas, herbaceous borders, a wildlife pond, trees and wetland plants, along with a vegetable plot. She has been gardening, reading, researching and photographing plants for over twenty years and her website is a popular resource for gardeners young and old.