At some point, you’ve probably scoured the internet in the hopes of finding a solution to the slug pest problem. Like most people, you were probably delighted at the plethora of results that claim to offer ‘great’ solutions to try. Maybe you’ve tried every hack and are just about confident with your chosen fix. But are you really sure it works? There seems to be a list of common slug repellent hacks circulating. And it’s about time someone shared why you shouldn’t be using them.

The RHS conducted a research study in 2018 finding that common home slug control remedies, including crushed eggshells, copper tape, pine bark mulch, wool pellets and horticultural grit to be completely ineffective. We decided to put their finding to the test in our own video, to see if these methods really do protect your plants from gastropods.

Do these Slug Control Methods Actually Work?

Read on to find out why these and other common slug repellents don’t really work…

Salt

An obvious choice for many people would be to throw some salt on the slugs or around your plants. A straightforward solution, however, with not so simple consequences.

While it may be an obvious answer in the grand scheme of things. It’s also an obvious ‘no-no’ to well-versed gardeners who understand that excessive salt is damaging to plants. The odd sprinkle of salt may have minimal effect to plants initially.

However, over time the more this method is used to deter slugs, an increasing amount of salt will build up within and around the growing medium of the plants and penetrate deeper into the soil with wind and rainfall.

Excess dissolved salt in soil can be very harmful to plants, through osmotic influence. Simply put, instead of taking up water, your plants will be losing it.

Left dehydrated and lacking nutrients.

The other harm to plants salts can cause is through ion toxicity. Plants take up sodium and chloride ions from dissolved salt particles which eventually travel to plant leaves causing burnt leaf edges and scorching.

The Slug Beer Trap

This method goes by the premise of the yeast contents within the beer attracting the slugs. With the hopes of the slugs becoming intoxicated after drinking it and therefore drowning in the liquid trap.

While it’s true that the yeast does attract the slugs, this method also seems to be counterproductive. Think about it, if your garden is infested with slugs and snails, surely the last thing you want to do is attract them using a bait, from as far away as 200 yards?

The truth is, this slug deterrent method isn’t guaranteed to work. In many cases, a sip of the beer is enough to satisfy the slugs and they’ll slide away off to look for other food sources in your garden.

The problem is that beer acts as too strong of an attractant, for a method that isn’t guaranteed to work.

Which means gardeners could end up with more slugs and snails than they originally had! Not to mention how this method is also damaging for the animal ecosystem that relies on slugs for food. If the beer trap was to work, it would still cause issues as predators such as birds or hedgehogs could come across the traps.

Whether you readily buy beer or for the sole purpose of this, it’s likely a waste either way. Drink your beer, don’t bother sharing it with slugs.

Crushed Eggshells

One of the most common slug deterrents hack you’ve probably come across is the old crushed eggshells trick! This method supposedly works with the belief that when an uncooked egg’s shell is crushed. The edges are sharp enough to hurt slugs should they decided to slide over them.

So, when gardeners spread the eggshells around their beloved plants, the crushed shell pieces are to form a protective barrier that slugs and snails should know better than to cross. And hopefully, if they did try, they would hurt themselves in the process and be unable to complete their journey, right? Wrong.

A quick search of the web and you’re sure to find plenty of crushed eggshell experiments that falsify this hack.

Not only have they shown that slugs crawl over eggshells without hesitation, some even proved that eggshells, in fact, ATTRACT slugs into the garden. It’s suspected that odour and slimy texture produced by an eggshell’s membrane is the cause.

Slugs will happily cross over crushed eggshells and back again to get their hands on your plants. We suggest you put them to better use and save them for your compost bin.

Copper Tape

Copper tape is a method subject to much scepticism when it comes to slug control. The general claim is that this metal reacts with the slime produced by gastropods (slugs and snails) to create an electric signal that gives them an electric shock.

If you were going to question any slug control method, then this is definitely the one. Many gardeners who follow this method are putting a lot of faith into a claim that technically isn’t backed up with scientific evidence.

While there’s also that copper tape has repelled slugs under lab conditions, nobody is gardening under lab conditions.

Within our own tests, copper tape proved ineffective at repelling slugs and there were no signs of shock or unpleasant feelings while observing them.

Wool Pellets

Wool pellets are not to be confused with slug pellets. Although they’re similar in design, they work differently. Wool pellets are made of 100% raw compressed sheep’s wool that is compacted into small pellets. The idea behind this method is that wool pellets will deter slugs and snails by absorbing the mucus they produce.

The problem with wool pellets is that a little rainfall makes them completely useless. Considering slugs are most active during and after a period of rainfall, this isn’t ideal. Especially in a climate of everchanging and unpredictable weather like the UK.

Several other problems with this method include the traces of salt that wool pellets might contain washing into the soil after rain. Which as explained previously, can have damaging effects to plant growth.

Gardeners have also claimed that rather than deterring slugs, wool pellets, in fact, have acted as a soft cushioned mattress for slugs. Giving them a place to rest and make a home of while munching on their plants.

Lastly, we can’t forget to mention how notorious wool pellets are for their awful smell.

Don’t ever open a packet of these inside your home!

Pine Bark Mulch

There are two main reasons behind using pine bark mulch to control slugs and snails. Gastropods do not like to travel across extremely dry surfaces because they will lose essential mucus.

However, much like wool pellets, pine bark mulch only serves to encourage slugs to travel towards your plants after contact with rain and moisture.

Even without rainfall, the coarsest of bark mulch clippings fail as plant slug protection because they naturally trap moisture for plants.

Creating the ultimate haven for slug and snails to hide, lay their eggs and destroy your crops.

Horticultural Grit

This method supposedly works with the idea that the harsh texture of finely crushed horticultural grit repels slugs from travelling over it.

Horticultural grit is probably one of the simplest methods, aside from salt. However, much like every other method with claims that harsh surfaces will cut and damage slugs to prevent them from travelling on its surface.

It forgets that these slimy creatures produce their mucus with the sole purpose of being able to move across a range of harsh surfaces.

In fact, we recently found a video that shows slugs effortlessly gliding across the surface of sharp knife edges. So methods like this and crush eggshells don’t really stand a chance.

Slug Pellets

Finally, we have good old, or should we say bad old slug pellets. We wouldn’t call these a hack, but they are a very well-known method of slug pest control that was recently banned for sale and for use.

Wondering why?

You might want to read up on why slug pellets are dangerous for children, pets and wildlife.

Slug pellets are a small, round compressed mass containing substances that are poisonous to slugs and snails. While this might seem like the perfect solution at first, they require excessive amounts of care with use because of how dangerous they are. It’s almost not worth using them.

We know, of course, that you wouldn’t intentionally put slug pellets near your loved children, pets and hopefully wildlife! But let’s not forget, that with a bit of rainfall, slug pellets melt into slush and essentially become ineffective.

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Monalisa

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8 Common but Questionable Slug Repellents