Thanks for the advice, but I try to use little to no chemical at all.Metaldehyde is the answer. Sprinkle some around in the garden and enjoy the sudden lack of slugs and snails.
pier
Metaldehyde is dangerous not only for slugs, but also for a lot of animals, so I won't use it.
The only chemical I use is "Ferric phosphate", which is relatively "safe", to try to reduce the slug pressure (because each year in early spring we have a LOT of slugs... and a few snails).
As I said, I don't want to eradicate them, I just want them to not eat everything.
Since we added a lot of mulch and wood in our garden (to feed the soil and enhance it), we have more insects than ever (centipedes, woodlouses, ground beetles, ladybugs...) but we also have more slugs of course
We also have a lot of different mushrooms.
Slugs are not an enemy, they are a part of the whole system. They are in fact a big help in the garden, they decompose organic mater, they suppress pathogenic fungus and reduce garden diseases. I don't want to eradiacte them.
Next year I will grow more plants in my tobacco and vegetable beds to feed the slugs, and I will transplant my plants only when they are a bit stronger (slugs love young and fragile plants, as much as dying plants).
It's all about experimenting, time will tell.
@Knucklehead : the pictures were taken during the night, while we were hunting for them (see picture bellow)
We have different kind of slugs, here are some small bright ones on our chards :

And now a plate filled with slugs, from one hunt (not for the faint of heart) :

I am really happy to see more insects and more life in my garden, it means that it's alive.












