My first line of defense is GARLIC!
I have no measurements for this. Place garlic cloves in blender and chop very fine.
Put the chopped cloves in a jar and add enough water to make a good amount of liquid.
I pour this mixture around the plant being eaten. This year I am going to try pouring the mixture around the garden bed to see if this keeps them out of the bed.
I keep this liquid tightly capped in the fridge to use at a later time.