I just came across this article regarding slugs you might find helpful
http://eartheasy.com/grow_nat_slug_cntrl.htm

Copper and Diatmaceous earth seems good all around help
Very interesting topic

I have experimented with the copper tape (wire isn't wide-enough IMO) with 'some' benefits. But it all depends on having the copper tape in the right place in the right time.

The best results come from the baits such as Sluggo and such but if she is opposed to using it then the small boards and salt shaker approach works best for me.

Dave

PS if you search 'slug control' here you can read lots of different tips and techniques and effectiveness

Ah, well. I searched for copper but didn't have any matching titles here.

I'm interested in no-effort solutions because my mom is too busy to tend to her garden, otherwise she would do it herself already. She tried coffee and crushed eggshells. It didn't work but I'm not sure if it's because she did it once and didn't follow up. She also used the beers sometimes, then forgot about it.

She's just busy. So the solutions that would require her to reapply it is out of the question because the slugs and snails will just bounce back when she stops.

I'd like to set up the copper (if not wire, mesh?) all around her garden, and take care of the predators myself inside the garden with baits, etc a few times until they're gone, then let it be. But my mom won't go for it if it isn't effective even if I offer to buy it myself.

She's grown suspicious of the claims by companies about the insects. Such like that sonic wave machine that supposedly drive the spiders and/or mosquitoes away by creating sound frequency they don't like. She got it and it didn't work.

I'll continue to research it when I have time.

EDIT:
I heard copper will repel snails, is this true?
I was a little disappointed to learn that the banana slugs weren't repelled by her copper. I'm not sure if it's because her copper is too small or poorly designed. We have numerous banana slugs around here, and they're main problem for my mom's garden. Slugs are huge here.

This post was edited by Aindra on Wed, Jan 16, 13 at 14:14

beer traps and diatomaceous earth are your best bets for slug control. Beer traps being the best.

There are YouTube videos showing how to set up a double wire system - and showing that it works. Do a search.

I'm trying to find a double wire video you speak of but ones I found is the electric wire fence for slugs, not copper wires.

Also, I did find one video on there that says to be careful about purchasing cheap copper tapes. Some are pretty bad that it doesn't work on repelling slugs. I'll have to keep that in mind.

It's confusing subject. It seemed like half videos proved that it works in repelling slugs, and other half proved it didn't work. I did notice the difference in design between good and bad so I'll have to look into which design works best.

I think maybe copper need to be cleaned once in a while; maybe the film develops over them, making it possible for slugs to cross them. That would explain why some people claim they saw some slugs traveling over copper bands on trees.

I realize that both beer traps and diatomaceous earth seems to be favourite among you. I just don't think that'll work for my mom. She lives next to the forest park, it's five or six meters away from her garden. That's source of the snails and slugs so even if we kill the locals, more will come from the park.