I just moved to Florida and have many plants in my yard and landscape that I want to learn to care for. I have two very pretty hibiscus that have the most enormous grasshoppers on them. I swear these grasshoppers are nearly 2 inches long! I don't see any damage to the hibiscus. Are these harmful? Do I need to go pick them off? Is there an environmentally friendly way to get rid of them and not have them return?