Hoya

Hoya is a genus of about 200 to 300 species of flowering plants in the family Apocynaceae, commonly known as wax plants or wax vines. Native to Asia, Australia, and the Pacific Islands, Hoyas are largely tropical, epiphytic or lithophytic vines that grow on trees or rocky substrates. They are prized for their thick, succulent leaves and for their umbels of small, star-shaped flowers with waxy petals and a cup-like corona, often highly fragrant.

The genus has long been associated with the former separate family Asclepiadaceae, and modern classifications place Hoyas in Apocynaceae, subfamily Asclepiadoideae. The group comprises many cultivars and hybrids developed for ornamental use.

In cultivation, Hoyas are popular houseplants. They prefer bright, indirect light, well-draining potting media, and a dry period between waterings. Overwatering can lead to root rot; they dislike cold, wet conditions. Many species tolerate periods of neglect and benefit from humidity and a stable indoor temperature.

They root readily from stem cuttings or division; aerial roots help support the plant in native habitat and can aid in potting onto trees in cultivation.

Flower clusters are enduring and come in white, pink, red, yellow, or purple tones, frequently with variegated cultivars. After flowering, the plant often does not form many new buds until stress-free conditions return.

Notable species include Hoya carnosa, Hoya pubicalyx, Hoya kerrii, and Hoya australis, many of which have popular cultivars such as variegated leaves (for example, H. carnosa 'Krimson Queen' and 'Krimson Princess').