Answer: Nothing you spray is going to get rid of the holes in your hostas. You cut off the leaves if the holes annoy you. I'd be careful about spraying hostas. Not only can they be sensitive to whatever you spray, you'd most likely be wasting your money on spraying something you cannot see and cannot identify. Just for future reference, here are the most common problems associated with hostas:
Slugs and Snails
Slugs and snails are nocturnal foragers and are the most common pest of hostas. They eat small round holes in the leaves. By beginning an abatement program early in the spring, slugs may be easier to control. Look for silvery slime trails in garden beds to determine if slugs are present. They may be spotted during daylight hours or in the evening by using a flashlight. Since some plants are more susceptible to slug injury, check around those particular plants to detect slugs. Thin-leafed hostas and those with leaves growing close to the ground are most susceptible to slug injury.
Chemical slug pellets and baits that contain metaldehyde are widely available commercially, however label directions must be followed carefully. A product came on the market in 2000 that shows some success in slug control; it contains iron phosphate, which is less toxic to animals and birds than baits containing metaldehyde.
Beer traps are widely used, albeit only moderately successfully. Place a small shallow container, such as a jar lid, level with the soil and fill with beer. Slugs are attracted to it, crawl in, and drown.
Other methods can be used, though they show limited success. Copper strips sold in garden stores and catalogs may be used to surround plants. The use of gritty materials such as diatomaceous earth scattered on the soil surface is also used. Other traps may be made by laying wet newspapers on the ground overnight. Check beneath these the next day to find slugs that have taken refuge from heat and sun. Kill the slugs by dropping them into a 10?20% solution of ammonia and water. Salt will also kill slugs if applied directly to them.
Black vine weevil adults chew irregular notches on the edges of hosta leaves. The black vine weevil larvae that feed on the crown and roots, however, do the most serious damage; symptoms of injury include yellowing and wilting of foliage.
Deer, Rabbits, Voles, and Squirrels
Deer can eat all your hosta plants in one evening, leaving just the stalks standing. Ten-foot tall fencing and trained guard dogs are the only reliable method to keep them out of the garden. Gardeners also use deer repellant, a bitter-tasting chemical that is sprayed on the leaves. These products need to be re-applied after several rainfalls. Motion detector garden sprinklers have also been used with some success.
Rabbits occasionally eat young shoots in the spring, and sometimes bite off flower scapes. Squirrels will eat hosta leaves during a drought, and sometimes dig up plants. Voles chew on the roots of hostas, and a heavy infestation of voles may kill plants. Wire cages made of hardware cloth encircling the hosta roots may deter them.
Hope this information is helpful!
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