I don't know where you are or the conditions in which your impatiens are planted. In California we usually make sure they have sun, but mostly shade and that they are well watered. Just the right combination for snails and slugs. Try putting out a pie tin full of beer in the evening. Check it the following day for any dead slugs or snails. the beer is safe around children and pets as is Sloggo. D. E. is also safe. Don't use products that might be harmful to children or pets.