Kingdom: Plantae
Clade: Angiosperms
Clade: Eudicots
Clade: Asterids
Order: Boraginales
Family: Boraginaceae
Genus: Symphytum
Species: S. officinale
Binomial name: Symphytum officinale
Synonyms: Symphitum officinale
Common names: Common comfrey, True comfrey, Quaker comfrey, Cultivated comfrey, Boneset, Knitbone, Consound, Slippery-root.
Symphytum officinale is a robust, perennial flowering plant in the genus Symphytum. There are thirty-four other species of Symphytum, all known as comfrey. It is a plant native to Europe but has been introduced to many countries where in some it has become invasive. In New Zealand, its wild habits are damp, often shady areas on roadsides, bush edges, near streams and rivers. Most Symphytum cultivars prefer full sun.
Symphytum officinale forms clumps of erect stems (30–120 cm high) bearing elliptic leaves that are >25cm in length. The leaves are alternate, margins are entire, hairy, and have prominent veins, hairy on the underside and there are narrow wings that originate from the base of the leaf blades. The Russian comfrey (Symphytum x uplandicum does not have these wings on its stems. The stems are covered in hairs
During spring and summer, it produces terminal clusters of nodding, tubular-bell-shaped, purple, pink or cream. They are 5-lobed and are 12–18 mm in length. They have 5 stamens and a long style topped with a stigma.
Comfrey's use as a medicinal herb is controversial as it contains small quantities of toxic alkaloids which can have a cumulative effect upon the liver. It is most frequently used topically for compresses and salves.
The hairy underside of a leaf.
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