Dittany

Dittany is a magical plant, and one of the most useful healing herbs and restoratives there is. Its pink leaves are cut when the plant is in full bloom and go into potions from there; dittany mixed with silver will stop a werewolf bite bleeding a victim to death, though it does nothing for the lycanthropy itself. Distilled as Essence of Dittany it gives off a greenish smoke as it works. The plant is also known as burning bush, and it will now and then release flammable vapours, which is worth knowing before handling it. One Thousand Magical Herbs and Fungi covers it, and Hogwarts fifth-years study it in Herbology.