How to stop slugs invading your home

Telegraph

25-06-2025

The RHS has been trying to persuade us for quite some time now that slugs are our friends, not pests. But when I nip into my basement kitchen for a glass of water at 11pm and spot a couple of them slithering around near the fridge, or, come morning, find their slime all over my living-room carpet, it's hard to think of these clammy creatures as pals.
It's one thing them eating my tomatoes in the garden, quite another to have them infiltrate my home.
There are about 40 species of slugs in the UK and they are estimated to cause around £8m in damage to crops each year – not to mention my soft furnishings. Professor Keith Walters, of Harper Adams University, has studied the behaviour of slugs and reveals: 'We found that when a slug detects another slug, it changes its behaviour. It travels more slowly, covering shorter distances, and has a bias to its turning angle… They travel in a circle and congregate.'
So, those slimy trails forming circles on my carpet mean, horrifically, that there has been more than one slug slithering around in my house at night. But apart from understanding their behaviour, what can we do to stop slugs coming into our homes?
Manage damp areas
Slugs are nocturnal and are attracted to damp environments. Unable to retain their own moisture, they seek out new sources constantly, so any damp areas in your home at night will present a haven for slugs. And they love the dark. 'Leaving a low light on in the kitchen overnight can sometimes discourage them from entering,' says Josh Novell, Director of Polhill Garden Centre. 'It won't solve the problem entirely, but it can be part of a broader deterrent strategy.'
If this feels a bit like leaving a night light on for our slimy friends, Tony King, pest control expert and owner of The Pied Piper, has another suggestion: 'Operating a dehumidifier, particularly in basements, crawl spaces, or bathrooms, can reduce the indoor environment's attractiveness for slugs. You should also consider inspecting for any leaks under sinks or in indoor utility areas.'
Seal access points
Those little critters are getting in somehow, so looking for holes or gaps that slugs could use to gain entry is key to keeping them out. 'Thoroughly inspect the exterior of the house, especially around doors, vents, pipe entries, and even minor openings in the foundation,' says King. 'Slugs can squeeze into cracks less than 0.5cm wide, so plugging these points of entry with silicone-based caulk, expanding foam, or door sweeps is required.'
Novell agrees this should be the first line of defence. After all, if slugs can't get in, they can't become a problem. 'If you're finding slugs indoors, the first and most important step is to identify and seal their entry points, including under old doors, around pipework, or through cracks in walls – particularly where pipes exit the building or where floorboards meet external walls,' he says.
Use copper tape
Anyone who grows anything in their garden will be familiar with a slug problem and has probably used copper tape to stop the creatures eating their plants. And if it works outdoors it can work indoors too. 'I recommend placing copper tape across thresholds or baseboards,' says King. 'Slugs receive a weak electrical shock from copper, so it is a natural deterrent.'
The only issue I see with this is having copper tape all over my kitchen, as I have numerous possible entry points in my basement. But, with Novell offering a good point as to why it's preferable to other solutions, I'm willing to give it a go. 'Copper can be used either in the form of tape or strips placed near known entry points,' he says. 'It's a chemical-free and pet-safe option that works especially well alongside other prevention measures.'
Sprinkle salt
This is probably the most commonly known way to deter slugs and it's still used by many homeowners with a problem. However, it's not the best solution, according to King: 'Salt barriers are conceptually good, but they do not work well for long-term use indoors because of the mess issue and potential damage to flooring or attracting moisture.'
Novell agrees, adding: 'Salt should be used carefully indoors. Rather than sprinkling it across your floors, try applying it directly to the edges of known entry points or placing a barrier line near baseboards.' He also offers another possible solution, though not one as natural or as harmless as salt. ' Slug pellets, which contain metaldehyde that kills the slugs, can be effective too, but it's important to place them outside and under cover to avoid accidentally harming pets or wildlife.'
It's worth pointing out that the slime slugs leave behind can also contain parasites that can be transmitted to pets. Thankfully these parasites aren't harmful to humans, but be sure to clean up any trails by sprinkling baking soda directly on the residue and hoovering it up a few hours later.
Clear debris
As we know from all those holes in the leaves of our plants, slugs feed on vegetation, so all those lovely houseplants you keep near walls may be attracting slugs inside, enticing them to slither through gaps for a nighttime munch.
'If slugs are getting in, the chances are they're thriving just outside your home,' says Novell. 'Look for damp, overgrown areas near windows, vents, or doors, under a dense bush or against a wall. Keep vegetation trimmed back, clear away leaf litter, and try to reduce moisture near access points.'
But plants can be helpful for keeping slugs at bay, too; choose the right plants and you might just win the battle. 'There are plants that slugs dislike,' says Novell. 'Planting things like wormwood, rosemary, rue, and fennel near your back door or under ground-floor windows isn't a silver bullet but it does work as a passive deterrent.'
Take the natural approach
If, like me, you're fed up of finding slugs in your home but like the idea of using natural slug repellents, peppermint, cedarwood or cinnamon essential oils are thought to provide pleasant deterrents, while ensuring your home is kept relatively clean and tidy will also help.
One final method of beating slugs for good? Novell recommends booby-trapping their path: 'Rough textures like crushed eggshells, coarse gravel or sheep-wool pellets placed near entry points are uncomfortable for slugs to travel over,' he says.