I’ve been experimenting with various ways over the past few weeks to keep slugs and snails off the veggie beds. The internet isn’t short on ideas about this topic. Hereby I’m summarising the methods I’ve tried so far and my observations and conclusions.
Beer trap
Place a container full of beer close to your veggie garden. Slugs and snails are attracted to beer (or sugary liquids in general) and will crawl into the container. There are different techniques suggested how to set up the container to prevent the slugs from climbing out.
Some sources suggest that you should have a trap every few meter to make this trap work. There’s also a timelapse footage shared as an evidence that slugs might be attracted but most of them will climb out. Exactly what happened in my case. I’ve tried both beer and sweet water, didn’t make a difference. I caught a huge wasp, though. Finally, some say, eventually you will attract more slugs than how many would show up otherwise.
Physical barrier around the plants
Mulching with grit or placing brambles around the plants will create a barrier for slugs to cross. Didn’t work. I had a chance to observe for long minutes how a slug happily climbed over a spiky bramble cut with no problem. When planting new seedlings, I had have hurt myself though with those spikes.
Natural repellent substances
I observed content slugs on peppermint, rosemary and chives — all of which they should hate and avoid. Some recommend making a water dilution with strong aromatic essential oils. I repurposed our summer insect repellent and sprayed some directly on munching slugs — with no effect. A few days later, when I picked some of the mint leaves and chewed on it, I ate my own dogfood though.
Natural predators
"You don't have a slug problem, you have a duck deficiency."
goes the famous permaculture saying. I’m currently unable to host ducks in the garden but I was curious to see how to collaborate with other natural predators, such as wild ground beetle, slow worm, birds, toad, and hedgehog. I already observed the presence of slow worms near the veggie beds — I have recently built a hideout that I believe can attract them. There are sparrows and common black birds around, although they primary hunt during the day when slugs are hidden. We found a toad the other day on the other side of the garden — we are currently building a little pond close to the beds and hoping that it will attract wildlife including toads. Birds already enjoy the bath. Hedgehogs and ground beetles I haven’t observed yet.
Night hunt
The most effective method to date I found was to go for a night hunt and pick the slugs up. It’s labour intense but effective. I observed slugs make their move when it gets completely dark and it gets humid at soil level. I set off for a hunt each day around 11pm, and check the herb garden and the raised beds. I now can identify at least three different varieties of slugs in the garden: the black slug, the Spanish slug, and brown field slug. Our first motivation was just to store the collect slugs in an in-situ compost bin and every now and then take them out to a wild area. In the meantime we learnt that slugs and snails die within a few days in the compost bin. At the moment I don’t have a better strategy sadly. I pick them with honest respect and say a prayer to the passed ones.
It’s been about two weeks now that I go for a night hunt. The number of slugs and snails is slowly decreasing, although it’s highly influenced by the weather. After rainy days their show-up rate is much higher.
Cutting the grass
Finally, when we cut the grass around the beds for a different reason, we realised that we removed the hides of the slugs. The short grass forces them to look for other shelters and makes them more exposed to their predators, including me.