Hi to You!
Last night, I just saw on Amazon.com that they had an offer for free shipping on "Diatomaceous earth", that is used for a natural killer/prevent-er for slug control for people who enjoy growing "hostas", and other plants that slugs can destroy.
It's put out by "Green Sense".
It was offered in 20 lbs. bags, With FREE shipping.
You can sprinkle this all around your plants and it is not harmful or poisonous to any warm-blooded animal.
It's 100% natural.
It's fossilized sea animal creatures.
This works by being like broken glass "sharps", that cut up, and/or irritate the slugs that come in contact with it.
When the slugs get cut up, they succumb to infections and die, or dehydrate and die.
This material is also used in pool filters, but don't get the pool filter grade, it is polished, and won't be as effective as the garden grade sold for slug control.
Check out amazon, in the garden, "pest control" sections or just garden products.
I'm getting some to use next spring on my hosta and hydrangeas.
Hope this helps,
Research and personal experience