Background...

I have a mini 4-tier plastic covered greenhouse... The plastics got damaged... but I hate the greenhouse anyway because the last couple of years, it has let in those slimy little monsters (slugs / snails) - no matter how much repellent/killer I put down.

I'm growing in my parents garden, so there is only one place I can put the greenhouse, and that is next to the fence... so I'm not really surprised that the beasts can get in...

If I had something on a lower level, I think I could pretty much store it anywhere... but I want something that'll protect my plants... and I think I've actually gone a little paranoid.

Last year, I bought and tried out the smallest piece of Shocka Mat - it's brilliant, so I will be putting this underneath any plants I grow (it means that my guinea pigs can run anywhere they want in the garden without risk of getting poisoned etc)

The Question

What do you recommend as the safest method of protecting my plants against slug/snails, where my plants can be kept warm?

I've looked into other style greenhouses, including blow-up ones, temporary ones, pop up ones, clotch tunnel thingies... other mini greenhouses...

But maybe I'm just paranoid?

Let me know your thoughts, ANY comments will be helpful (even if you want to laugh at me and call me stupid... but the first yr I tried gardening, we had a huge infestation of those 'slimers', and they damaged/ate EVERYTHING, literally [including onions? They left those till last?])