Acorus calamus

Acorus calamus has been cultivated across Europe and Asia for millennia for its aromatic properties — the rhizome contains calamus oil long used in traditional medicine and perfumery. In aquatic settings it grows as an emergent plant with long, upright, slightly wavy leaves that can reach 150 cm above the waterline. In the aquarium or paludarium it is strictly a marginal species, with its rhizome at the waterline or just below in shallow substrate. It is cold-hardy and dies back in winter, regrowing strongly each spring.