Der Efeu ist ein immergrünes, kriechendes oder kletterndes Holzgewächs und kommt in vielen verschiedenen Formen vor. Die dunkelgrünen Laubblätter nichtblühender Zweige sind meist 3- bis 5-eckig gelappt und meist weiß geadert. Die Blätter blühender Zweige zeigen dagegen eine ganzrandige, längliche Form. Die gelblichgrünen Blüten stehen in kugeligen Halbdolden und bilden als Frucht kugelige Beeren, die unreif von rötlichvioletter, reif von schwarzer Farbe sind. It is an evergreen climbing plant, growing to 20-30 m high where suitable surfaces (trees, cliffs, walls) are available, and also growing as ground cover where there are no vertical surfaces. It holds on to tree bark and rock by means of short adhesive rootlets. The helix part of the name refers to where there are spirals in the leaves. The flowers are produced from late summer until late autumn, individually small, in 3-5 cm diameter umbels, greenish-yellow, and very rich in nectar, an important late food source for bees and other insects; the fruit are small black berries ripening in late winter, and are an important food for many birds, though poisonous to humans. The seeds are dispersed by birds eating the fruit.
