Slug food?

Last year the gov said ‘Never again’ after coming second in the battle against slugs and snails, resulting in decimated plants.
This year I decided I would give it a go, and planted some beans in pots.
So far the slugs have been absent due to the lack of rain, but the problem has been poor germination rates. Out of 45 climbing beans planted less than a dozen have produced plants.
These are the second lot of seedlings.