I guess snails and slugs have some purpose in the grand scheme of things, but when they start destroying vegetable crops, ornamentals and leaving silvery trails, it becomes difficult to see just what good they may serve.
There are a few natural cures that have some success, although I once knew an organic vegetable grower who used to rise early and collect snails from his crops using a torch and a bucket, declaring this was still the most effective method of control.
If protecting a small area, surround the area with a circle of powdered chalk. It has been suggested that snails and slugs will not cross the chalk.
The owner of this suggestion insists that the brew must be Coca Cola. Coke poured into jar lids and dispersed around the garden will, because of it’s sugary content attract these molluscs. It seems the acids in the soft drink will destroy them when they slither onto the
lids (It does this to snails and we drink this stuff?)
Pour beer into a large saucer (or an unused Frisbee) and leave in a
shallow hole in the garden, allowing a lip around 6mm to project above soil level. It seems the alcohol intoxicates and then commences to break down their bodies. (Not a drinker, but know some who would declare this a waste of good beer)
Plain cooking salt sprinkled on snails and slugs will result in instant destruction. Try to avoid the tendency to bury the victims in salt. A small amount will suffice.