Keep this in mind! Slugs will not crawl over "crusher dust" or dolomite (crushed sea shells-from Aquarium shops). The sharp tiny rocks evidently tear open their bellies! GOOD!! I finally put in Hostas again two years ago, along with daylilies, and not a slug anywhere! Of course, then a deer got through my fence, and then there certainly were no slugs on what had once been Hostas! LOL. I have never tried ammonium spray, so I don't know if it just keeps slugs away, or kills them. I think I will try a mild salt solution spray for other plants because I know the slugs disintegrate right in front of your eyes if you sprinkle salt on them. Yes I LOVE IT!!! Lock me up, I don't care!!!!! LOL.