Hoya is a very large genus of tropical to subtropical plants found in Australia, Polynesia, and Asia. With over 200 species, this genus is tremendously diverse, and numerous interesting and rare examples can be seen in nature. Several species are propagated by gardeners for use in outdoor gardens, as well as indoors as houseplants. People can obtain Hoya seedlings or cuttings from nurseries, garden suppliers, and through exchanges with other gardeners. These plants are highly suitable for beginning gardeners, as they are very easy to cultivate.
Members of this genus have thick, almost succulent leaves and some are formally considered succulents. The leaves vary in size and shape from large, simple, broad leaves to small, heart-shaped leaves. All Hoya species produce flowers in clusters, and the blooms have distinctive waxy petals and a five-pointed star shape. The flowers can be white, yellow, pink, or some combination of those colors and may appear in anything from loose sprays to tightly packed balls, depending on the species.
Also known as waxplants, waxflowers, or waxvines, Hoya species are often climbing or creeping plants and can grow very quickly in conditions they find pleasant. Other species are more shrublike and can take the form of a low groundcover. For gardeners working outdoors, United States Department of Agriculture (USDA) zones nine through 11 are most hospitable to Hoya species. The plants need full sun and rich, well-drained soil. It is important to allow the plants to dry out between waterings, as they are sensitive to wet conditions.
For indoor gardening as houseplants, Hoya species prefer a warm, brightly lit area of the house without being placed in direct light. Although they can grow in low light conditions, they tend to grow much more slowly in dim light, and may not produce flowers as profusely or as frequently. The soil should be checked regularly to prevent the plants from drying out completely or becoming too wet, and in a dry home, spraying to increase humidity around the plants can be very helpful for Hoya cultivation.
People have been growing these evergreen plants for centuries. Some people consider them old fashioned, and some cultivars do indeed have an old fashioned look and feel. However, with hundreds of species to choose from, there are plants available to suit numerous tastes and an unusual Hoya species can be just as visually striking and interesting as a more exotic houseplant, in addition to being much easier to cultivate.