There are about 200 different species of Hoya in tropical and subtropical regions of the world and seven of these occur in Australia. They are climbing plants with fleshy leaves. As with other members of their family, the milkweeds, their stems contain a sticky, white latex.
Hoya australis is found growing naturally north from Grafton (NSW) along the Queensland coast to Cape York in rainforest margins and exposed, rocky areas. It is commonly known as the wax vine due to the wheel-like clusters of up to 40 exquisite porcelain-like flowers on each long stalk that appear in spring and summer. Each flower has five triangular petals and a central star-like crown and is delicately fragrant. The flower stalks originate from a knobbly spur on the stem and the same spurs produce the next season’s flower buds.
There are five recognised subspecies of Hoya australis, each differing slightly in leaf shape. The flowers of each sub-species also differ in colour from white or cream, with a pale pink blush or tinted with light green. The centre of each petal often presents a darker pink overtone. All Hoyas grow exceptionally well in cultivation provided good drainage is available. The vine is often trained to grow on trellises and fences although they the form a beautiful display in containers or hanging baskets. In frost-prone areas, they are best kept as an indoor plant. In all situations they flower most prolifically in good, filtered light conditions.