Salt kills slugs and snails pretty rapidly. If you’ve ever poured salt over an unlucky gastropod, you’ve probably watched, aghast, as they bubble, appear to melt and eventually shrivel up and die.
However, pouring salt on a slug or snail doesn’t actually melt them, though it may appear that way. But it does cause their bodies to go through a horrific (and probably excruciating) process that transforms them into a bubbly, shriveled and slimy mess.
But why does salt melt slugs, and is it a viable control method for these pests?
What are slugs and snails, and why are they considered pests?
Slugs and snails are gastropods, an ancient Greek word that literally means ‘stomach foot’ and refers to the unique anatomy of these slimy creatures.
Though distantly related to octopi and squid, the garden variety slug is definitely a terrestrial critter and is often found in cool, damp places. Their preferred habitat is gardens and flowerbeds, where they feast on both living and decaying plant matter.
As a result, slugs and snails are serious pests of several plant species, especially young and succulent plants. Seedlings and low-growing fruits, such as strawberries and tomatoes, are prime targets for hungry slugs and snails.
By scraping away at the plants with their rasping tongues, they can take large chunks out of the border of leaves and will ruin ripening fruits.
Slugs and snails are the no.1 nemesis of gardeners around the world, but is salt really the best way to deal with them?
Why do slugs and snails die from salt?
Slugs and snails have very thin, permeable skin so, when you sprinkle salt on them, water is rapidly sucked out of their cells via a process called osmosis. This starts to dry out the slug’s body which, in response, starts producing more slime to try to protect itself, creating the ‘bubbling’ or ‘frothing’ effect that makes them look as though they are melting.
Pretty soon, the slug will shrivel up and die of dehydration as water and air are sucked out of its skin by the salty, slimy solution that covers it.
Of course, this doesn’t happen if you get salt on your own skin, but this is only because human skin is far less permeable than that of a slug. If you’ve ever gotten salt in your eye or an open wound, however, you may be able to empathize.
Can slugs and snails feel pain?
The question of whether slugs, snails and other bugs feel pain is a controversial one. It’s not a subject that has been widely researched, partly because it’s hard to determine exactly how a slug is feeling.
Some studies argue that slugs and snails can’t feel pain because, while they do have a nervous system, they don’t have a brain. This theory assumes that the sensation of pain is generated by the conscious brain and is, therefore, the sole domain of vertebrates.
Others, however, have found evidence of pain responses in sea slugs and, even if they don’t experience pain in exactly the same way we do, they almost certainly feel extreme discomfort and/or distress when ‘melting.’
Pain and discomfort are evolutionary necessities for all sentient creatures – after all, how else would we learn to avoid things that cause us physical harm?
The jury’s still out when it comes to how slugs and snails experience this unpleasant sensation, but there’s a good chance they don’t like it.
Should you use salt to control slugs and snails?
You could use salt to control slugs and snails in your garden, but only if you can handle the karmic repercussions.
Death by salt is a hellish way to die if you’re a gastropod, and most people probably don’t have the stomach to deal with that amount of slime, anyway.
There are many other more humane ways to keep slugs and snails off your veggies that are just as effective, but a little less psychopathic.
Alternative methods of slug and snail control
Know your enemy and plan(t) accordingly
Slugs and snails favor certain types of foliage, including young, succulent plants and low-growing fruits.
If you want to keep slugs and snails away from your garden, there are a wide variety of slug resistant crops you can plant instead.
There are lots of easy and effective options for trapping and killing slugs.
One simple example is the beer trap. Bury a partially filled can up to the lip and wait for slugs to drink themselves to death. For this method to be effective, the beer (and dead slugs) should be emptied out and replaced every few days.
The great thing about slugs and snails is that they aren’t hard to catch and, when done regularly, hand-picking is a highly effective control method.
Inspect your plants for slugs and snails a few times a week and, when you find them, pick them off and drop them into a bucket of soapy water (or a 5-10% ammonia solution) to kill them quickly.
Alternatively, you can crush them and leave the bodies for the birds.
Poison bait and other chemical control methods
Poison baits and sprays may be a viable option for people desperate to defend their strawberry crop from large numbers of slugs.
Keep in mind!
However, chemical control measures should always be used with caution and they can be toxic to other animals, including dogs and beneficial insect species.
Install slug-resistant barriers
There are plenty of other substances that repel slugs and snails, including diatomaceous earth, lime, sawdust, wood ash, and copper striping.
You can use these substances to make a slug-proof barrier around your plants, but they may need to be replaced after a rainfall.
Salt doesn’t actually melt snails and slugs. Salt kills slugs and snails by mixing with the slime on their skin to create a highly saline solution. This rapidly sucks water out of their bodies by osmosis, causing them to bubble, shrivel, and die of dehydration.
It’s a guaranteed way to kill these slimy pests, but it’s pretty gross and potentially grossly inhumane.
Fortunately, there are plenty of other ways to control slugs and snails in your garden including hand picking, setting traps, planting slug-resistant plants and creating barriers around susceptible plants.