Some slugs feed on our hostas leaving conspicuous holes in the leaves. The holes usually are in the middle portion of the leaf blade and vary with the size of the slug. The holes may run along between leaf veins and can be sever enough to skeletonize an entire leaf or almost an entire clump. There seems to be no question that the preferred hosta types are those plants with the species H. plantaginea in the background.
We have three options if we don’t want slugs to eat our special plants. Ignoring them is not one of the options, but it may be something to consider if we don’t mind the occasional hole in our leaves. The first option is to give them something else they would rather eat. My slugs would rather eat lettuce and pulmonarias than hostas. So I may feed them some of those crops or just allow them to eat the tastier one in my garden.
Another option is to ward them away. Some nurseries have strips of copper all around their nursery or specific greenhouses. The copper seems to act as a barrier. The slugs don’t seem to like to cross it. It may be because they get a slight electrical shock from crossing it. However, it may also be because the copper is toxic to their system and they probably absorb some of it through their slime and skin. If copper is too expensive to buy in sheets, we can rejoice in that there is a government program that subsidizes our plant protection. They call it the U.S. Mint. They give us tons of copper for just pennies! Although lining our entire property with pennies may not be practical for us, one can certainly epoxy a ring of them together for placing on the ground to surround special plants. Other materials are also effective. One commercial product, Dead-Line, is great until it washes away in the watering or rain. I have found that fertilizer works as well as table salt for killing slugs. It also works fantastically well for circling troubled plants. I sprinkle a border of any cheap garden fertilizer about an inch wide and solid enough that the particles are slightly piled on top of each other or about 1/16 to 1/8 inch deep. All these will help keep slugs away from your plants. They will not protect them from the slugs already in the corral though.
A third option for slugs is to blast them into kingdom come. Here we have a huge arsenal at our disposal. Metaldehyde** and methiocarb** are two very toxic poisons. They are available in many forms. Fortunately or unfortunately, the Metaldehyde** breaks down more quickly in the garden. Both are sometimes used in baits that can be very effective. Use caution to make sure birds, pets and children do not eat or even play with the baits as these products are deadly to other life forms, too. Some of the baits are very similar in composition to dog food except for the poison so choose and use your baits with extreme caution. Other gentler, friendlier solutions are already in our kitchens. A 10% dose of either vinegar or ammonia is just as deadly if sprayed directly on slugs. Fortunately, both household chemicals can also be used by the plants as fertilizer in small amounts. The difficulty in using ammonia or vinegar is that you need to see them to spray them. This means either foregoing a little sleep in the evening, getting up early in the morning or making traps. My preference is the traps. Since slugs don’t like hot dry conditions, they usually hide when the sun warms up. Favorite places to hide include under a nice cool rock, board or mulch. Some people place two boards on top of each other with a small stick between. This gives slugs a nice comfortable place to crawl until the stick is removed and one stomps on the top board!
** Please follow label directions and all state and federal regulations on pesticide use.