If I go out at night I will usually see 2-3 slugs oozing circles around the bottom of the barrier but not crossing it. Nematodes are microscopic parasitic worms that feed upon molluscs but also risk killing non-pest garden species such as water snails.

I used the copper tape on the bottom frame of my patio door to prevent slugs from coming into the house and it is working very well.

Something drank my beer last night and must have eaten the trapped slugs as well, nothing in the trap, but my petunias were in tatters. Environmentally friendly gardeners who attempt to deter slugs and snails from devouring their vegetables with eggshells or copper tape are wasting their time, according to a study by the Royal Horticultural Society. I don’t believe in killing slugs–whenever man invades Nature by killing off it’s creatures, it creates an imbalance somewhere else (as we have SLOWLY learned).

I stopped slugs getting to my potted Hosta’s by smearing a layer of Vaseline round the top edge of the pots, this works extremely well, just got to make sure the leaves don’t touch the ground or other plants ! Have been trying out lots of ways of stopping slugs and snails and came to the same conclusion as yourself – copper tape on its own does not stop them. If you live in a city there’s probably more chance of copper tape having this effect than if you live in the countryside. Each barrier was laid in a complete circle around the base of the lettuce and after six weeks of nurturing the crop, and some early anxiety because they weren’t being nibbled to begin with, Hayley found there was no difference in the damage sustained by either the protected lettuces or the ones left to fend for themselves – without barriers – against the pests. Tried coffee grounds, egg shells and other rough surfaces (have even tried inverted wire brushes – again does not work).In the past I have had some pretty good success with a solution of ammonia sprayed on the slugs at night. Jones added: “Slug pellets do have their problems but they have been tested for safety and when used to their manufacturers’ instructions the risks are quite minimal.