Credit: © Claire Schroeder

In the latest in a series of articles about current conservation issues, experts at natur&ëmwelt, a leading nature conservation NGO in Luxembourg, spoke to about slugs and their often fraught relationship with gardeners.

Natur&ëmwelt volunteer David Crowther helped collect the relevant information from the NGO for this article. Slugs seem to be all over the gardens this spring- why is that?

Natur&ëmwelt: Because it’s been an old-fashioned, slow, cool, wet spring - unlike the warm, dry springs we’ve got used to in Luxembourg over recent years. And what is the connection?

Natur&ëmwelt: Desiccation and locomotion. Slithery, slippery slugs move best over damp, smooth surfaces. They don’t like having to negotiate dry, loose, sun-exposed ground. And that, as we’ll see later, is one of the key considerations if we’re treating them as garden pests. Are there people who do not regard them as pests?

Natur&ëmwelt: Who are we, Homo sapiens, the most destructive species on the planet, to decide what is or is not a pest? Okay, if you are a gardener, you’re not going to feel exactly well disposed towards these naked snails. Naked snails? That is an interesting way to describe them…

Natur&ëmwelt: Just quoting their German name: Nacktschnecke. Slugs are indeed one of many types of shell-less gastropods. What exactly is it that gardeners dislike about slugs?

Natur&ëmwelt: They’re voracious - the slugs, that is. They love eating delicate young shoots and plants, like the ones you’re cultivating so lovingly in your garden. They have a particular liking for lettuce. And they reproduce alarmingly quickly and abundantly. Tell us about their life cycle.

Natur&ëmwelt: Each slug is a hermaphrodite, but they still have to get together to mate. They lay large clumps of eggs, in the soil or in a shady spot. The eggs can hatch quickly or lie dormant over the winter. Do slugs have no natural enemies? If they move so slowly and are so ubiquitous, surely they would be easy to catch and eat…

Natur&ëmwelt: They’re easy to catch and would presumably make a copious meal, but hardly any animals will touch them. Hedgehogs and ducks will (Rent-a-Duck startup, anyone?), but virtually nothing else. Slugs are just disagreeably slimy, unappealing and unappetising. Have humans ever tried eating them?

Natur&ëmwelt: We’ve heard a story of Boy Scouts who experimented with a dish of slugs boiled in salt water. The verdict of those who were prepared to try the delicacy: chewy and tasteless. So, now we come to the elephant-in-the-room question: how do we rid our gardens of these “unwanted diners”?

Natur&ëmwelt: It depends how callous you’re prepared to be. The sensitive gardener will protect his/her delicate plants by surrounding them with loose, locomotion-inhibiting material, like wood chippings, sawdust, dry compost or crushed eggshells. It also helps to leave a small pile of pulled-up weeds to distract the slugs from your more valuable crops. Our best-practice recommendation is one of various forms of metal, plastic or copper “slug fences” which can be used year after year to deter the little beasties. And if one is prepared to take more extreme measures?

Natur&ëmwelt: Beer traps are popular. It’s an intoxicating way to drown, though the slimy, beery end product is still a disposal problem. The most effective tactic is undoubtedly to go out with a torch on a damp night and simply collect the creatures. And then? What is the disposal solution?

Natur&ëmwelt: Well, let’s assume you’re not the kind of person who simply tips a bucketful of slugs into the neighbour’s garden. Slug gatherers who can stomach it cut each one in half with a pair of scissors.  And then... Truth to tell, no one’s ever come up with a really satisfactory answer. Wherever you tip dead slugs, it’s going to be a mess, partly because some slug species are cannibalistic. Live slugs eat dead ones. Look, just dispose of the things in a way that won’t harm the environment - we won’t ask too many questions...