Common but Questionable Slug Repellents
13 July 2018 03:01
Gardening, crushed egg shells, how to protect against slugs and snails, slug pellets, slug repellent, slugs and snails, the beer trap
Image Source: Gardener’s World
As a gardener, at some point or another, you have probably scoured the internet in the hopes of finding a solution to the infamous slug pest problem. Like most people, you were probably also delighted at the plethora of results and articles that claim to offer ‘great’ solutions to try. Whether you have already tried and tested every hack known to man and are confident with your chosen fix or if you’re still on the lookout for the ultimate solution, we’ve put together a list of what seem to be the most obvious slug repellent solutions and explain why you shouldn’t be using them.
An obvious choice for many people would be to throw some salt on the slugs or around your plants in the hopes that once slugs come into contact with it, they desiccate. 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 as weather effects such as rainfall and wind take effect. An excess amount of salt, dissolved into the soil system through rainfall or watering become very harmful to plants either by osmotic influence or through toxicity.
Osmotic influence referrers to the process of osmosis, which is defined as:
“a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one”
In other words, when there are more particles in one area, a solvent (e.g. water) will travel from where there are fewer particles to more particles. In the case of salt concentration in soil, this would mean that the salt reduces the movement of water from the soil into plant root systems (with there being more particles outside of the plant’s roots), therefore affecting the plant’s access to nutrients and moisture.
The other harm to plants salts can cause is through ion toxicity. Sodium and Chloride ions separate when salt dissolves in water, which then causes chloride ions to be readily absorbed by plant root systems. These ions then are transported to plant leaves where they eventually accumulate at toxic levels which eventually appears as leaf burning on leaf edges, better known as leaf scorch.
THE BEER TRAP
Let’s say your garden is infested with slugs and snails, then the slug pest situation could be a slightly bigger problem for you and you may have possibly considered 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, in fact, attract the slugs, (it has been known to attract slugs and snails from a distance of 200 yards) 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 sufficient enough to satisfy the slugs and they’ll slide away off to look for other food sources in your garden.
The ultimate problem is that the beer acts as too strong of an attractant for slugs and snails, 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, feast on the beer saturated slugs and end up with alcohol poisoning.
Besides, let’s face it… Whether you already buy beer or you’re going out of your way to buy it in order to use it for this. It’s going to be a waste either way. Drink your beer, don’t share it with slugs.
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 the effectiveness of this method. 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.
Last but not least we have good old, or should we say bad old slug pellets. We wouldn’t call these a hack but rather a widely known method of slug pest control, that should really be on the decline. If you haven’t heard of them before, 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, that it’s almost not worth using them.
We know, of course, that you wouldn’t intentionally put slug pellets near your loved one and keep your pets out of harm’s way but our emphasis on the amount of care required to keep not only your children and pets safe but other’s people, their pets and general wildlife. Not sure what we’re talking about? Then you might want to read up on why slug pellets are dangerous for children, pets and wildlife.
Also, let’s not forget to mention that with a bit of rainfall, slug pellets melt into slush and essentially become ineffective.