Marrubium (horehound or hoarhound) is a genus of flowering plants in the family Lamiaceae, native to temperate regions of Europe, North Africa, and Asia as far east as the Xinjiang region of western China. A few species are also naturalized in North and South America.

Beautiful under old roses and in a dry garden, Marrubium supinum, commonly known as Scallop Shell, is one of the best evergreen ground covers for hot dry spots forming a dense mat of scalloped soft grey leaves, the texture of velvet. The leaves ascend the summer flower stems which carry whorls of hazy purple-pink hooded flowers. A fabulous drought tolerant foliage plant and one of the best greys. 40cm x 70cm.