Mentha cervina - A spreading herbaceous perennial with slender aromatic leaves. A great plant for the bog garden or along pond margins. I grow mine in a few centimetres of water and they love it. It overwinters under water in its natural habitat. A Mediterranean native, Hart’s Pennyroyal has been traditionally used as both a culinary and medicinal herb, with a long recorded history of use. It is a threatened species throughout most of its growing areas. Frost hardy, and will grow in most moist to wet soil types. As with all other mints, this plant can be invasive, so plant in pots or contained areas.