In the end, however, I'm afraid my main method of slug control is to go
out at night - some people say the best time is around 2 hours after
sunset - with a torch and a sharp knife. Over a period I find that you
really do get the numbers down. As anyone who has done this will tell
you, slugs also feed enthusiastically on the corpses of their fellows.
So if you resist the impulse to tidy these away you may find over a few
nights that you get quite a build-up of victims in certain spots. It's
nasty but it's certainly organic.

I'll vouch for it - myself and a pair of secateurs dealt with 100 critters
the first night, 70 the second 50 the third, then 30 then 20 then 10,
finally
it was difficult to find them in double figures.
I finally snapped when I realised nearly all the plants I had sown
direct into the flower beds had been grazed into oblivion by slugs. I was
sat on a low wall an hour after sunset contemplating what had become of
my night-scented stock etc when I started to hear a rising din of slurping
noises. A torch soon revealed a whole squadrons of slugs and snails
emerging from those cool, dark, damp places they inhabit.
I do hear that if you leave suitable objects on the soil that give
shade
and a safe place to shelter, slugs congregate under them and save you the
cost of torch batteries and nocturnal prowling - I've yet to give it a try.

Andy.