Bill wrote:

Last year I followed up on some University of
Hawaii research by sprinkling fresh coffee
grounds on my soil when the slugs got bad.

I read that they used a 2% caffeine solution, not coffee. Caffeine is a
powerful neurotoxin and at this dose would probably kill beneficials as well
as slugs. If coffee (a much lower dose of caffeine) could be used, that
might be worth considering. Where did you find your info?

Brina