I really think garden slugs and snails are tuned to know when you plant new seedlings - they must be watching from under some shrub!
This idea was sent to me from Susan who has great success with it - I have not tried it myself - I just can't imagine giving my porridge away.
If it came down to a choice between slug and lettuce or slug and porridge, I would choose the porridge every time.
It's all very simple to do and makes sense. Just place the porridge / oats around the new plants or along the border. If I was to use this idea I would make sure I had a relatively thick spread of porridge / oats.
I would also make sure it was slightly mounded as that may make it more difficult for them to climb over as the porridge is very dry. You can think of the porridge as a type of snail food.
The slugs come along and devour the porridge - this makes them bloat up and die!!!!
According to Susan in the morning birds come along and eat them all, a treat for the birds as they get their protein and grain all in one meal.
Remember when the birds have finished you can place the snail shell in your compost - everyone wins.