A scientific study shows that bean leaves trap bedbugs that try to cross them. Anecdotal reports exist that state that various essential oils will repel them, but a 2014 study found that a range of common oils do not affect bedbugs.
Tiny curved hairs cover certain types of bean leaves. These hairs impale the legs of bedbugs that walk over them and permanently trap them. Researchers want to develop a synthetic replica of these leaves to apply to bed legs and other areas that bedbugs commonly traverse. Synthetic repellents for other pests, such as mosquitoes, do not have any effect on bedbugs.