Though slugs are rarely welcome in a gardener’s backyard, the Royal Horticultural Society have not classified them as “pests” for years now.
That’s partly because less than a quarter of the species in the UK actually eat your plants, while all of the maligned molluscs provide a food source for the UK’s shrinking bird population.
For these reasons, British gardeners have been discouraged from using pellets to deter the critters.
Other methods, like placing a halved orange or melon skin in your garden or conducting torchlit searches at night, can remove them from vulnerable saplings without killing all of them off indiscriminately.
And, as BBC Gardeners’ World writes, a bulb of garlic can help too.
Garlic water can repel slugs
According to the publication, “A home-made garlic spray can be effective in deterring slugs and snails from your plants” if applied regularly.
Allicin, a compound in garlic, both helps to repel and, sometimes, kill slugs and snails, botanist James Wong wrote for The Guardian.
For that reason, he says, you should only apply it to the most vulnerable plants (young seedlings and tender-stemmed plants count).
To make the garlic water concentrate, Gardeners’ World writes, boil one bulb of garlic per litre of water (they did two bulbs and two litres) until they’re soft.
James Wong, meanwhile, recommends blending a bulb of garlic with 1L of water, letting the liquid sit for ten minutes before straining “for the chemical reaction that creates allicin to complete.”
James uses his blitzed, rather than cooked, garlic water as-is, but Gardeners’ World dilutes two tablespoons of their boiled concentrate per 5L of water.
Whichever method you choose, you can spray it on affected plants “just as night begins to fall.”
How much should I apply, and how often?
For targeted slug and snail management, you should apply it “liberally.”
Gardeners’ World says you should spray or water with it once a week or after rain.
Specialist growers Sienna Hosta agree: they say we should water our plants with the stuff once weekly from February ’til October, when slugs are more active.
We should reapply it more often after heavy rainfall.
