Apocynaceae

Hoya

Epiphytic climbers with thick waxy leaves and umbels of small, intensely scented, almost artificial-looking flowers. Pollen travels in paired sacs — pollinia, as in orchids — and in at least one species those sacs attach to the legs of night-flying moths. The family is Apocynaceae; sources still printing Asclepiadaceae are decades out of date.

Native to Tropical and subtropical Asia to Australia and the Pacific

Species

Hoya carnosa (L.f.) R.Br. 'Compacta'

Hindu rope plant

3 photographs

How Hoya generally wants to be treated

Species pages start from this and record only where they differ.

Light: Bright indirect, with some direct sun tolerated and often needed to flower. Too little light is the usual reason a hoya grows well and never blooms.
Water: Let the top of the mix dry before watering again. It is succulent-leaved and stores water, but it is not a desert plant — published work shows it takes up a good deal of carbon dioxide by day as well as by night, so it is not strictly CAM and should not be watered like a cactus.
Humidity: Moderate. It tolerates ordinary indoor air better than its reputation suggests.
Temperature: Warm, with a winter minimum of 50 °F (10 °C) — two of three sources give that figure and the third gives 45 °F (7 °C); take the higher one, since the cost of being wrong is cold damage.
Substrate: Very free-draining and coarse — an epiphyte mix of bark and perlite. It grows on trees, not in soil.
Fertilizer: A balanced feed at half strength through the growing season.
Propagation: Stem cuttings with at least one node, in a coarse mix or water.
Dormancy: None. Growth slows in winter with the light.
Common problems: Cutting off the old flower stalk. Do not: it flowers from the same peduncle again, and removing it removes next year's blooms
No flowers at all, which is usually too little light
Rot from a mix that holds water; it wants to dry between drinks
Leaf drop below about 50 °F (10 °C)
Mealybugs in the leaf axils, where they are easy to miss

Sources ¹²³⁴⁵⁶⁷

In the collection

Hoya compacta Hoya carnosa (L.f.) R.Br. 'Compacta'