Name similarity aside, the plant commonly called hyssop is a species in an entirely different genus than the water hyssop. Known as Hyssopus officialis, this garden hyssop is a woody, shrubby perennial with an upright habit that grows in relatively dry conditions. This is the hyssop mentioned in the Bible as a purification herb. Further complicating the issue is the fact that various species and cultivars in the Agastache genus are also known as hyssops. The name hyssop is sometimes given to plants with a history of medicinal or ritual use.