plectranthus
Refers to plants of the genus Plectranthus, often used in traditional medicine or as ornamental herbs. The name 延命草 literally means 'life-prolonging herb'.
Plectranthus is also popular as a foliage plant.
Compound of 延命 (enmei, 'prolonging life') and 草 (sō, 'herb, grass'), referring to the plant's traditional medicinal use.