By Karen Francis, Master Gardener In-Training, SCMG
Finally, after 4+ years of waiting, my Hoya carnosa (HOY-ah kar-NO-su) finally flowered. It was well worth the wait! Not only were the star shaped clusters of flowers (umbels) beautiful, they were fragrant. H. Carnosa is said to be an old-fashioned houseplant, which I can attest to as I received my cutting from my mom who has had her H. Carnosa for over 15 years.
Other common names for the H. carnosa are porcelain flower or wax plant as evidenced in the flowers and in the deep green leathery leaves growing on a vine that can reach up to 10ft. Some leaves have flecks of silver or creamy white, making it an attractive house plant even when not flowering. These plants are from the Asclepias (milkweed) family. They are native to Southeast Asia and Australia, and have been in cultivation for more than 200 years giving rise to around 900 known species, cultivars, and hybrids. It was named after an English botanist named Thomas Hoy ( 1750 – 1822), who worked as a gardener to the Duke of Northumberland in Middlesex in the UK.
To better understand the needs of this plant it is important to know how it grows in its native habitat. The Hoya is an Epiphyte, also called an air plant, which is a plant that grows upon other plants (trees), and gets its nutrients from the air, water and dust around them. An orchid is another example of an air plant as well as other succulent houseplants.
Some Common Hoya cultivars:
- Hoya carnosa ‘Variegate’ – This hoya produces leaves that are lined in white and pink, in addition to the green. Sometimes this plant will produce solid white leaves
- Hoya carnosa ‘Rubra’ – This cultivar, sometimes called Krimson Queen, has green leaves with creamy outer edges
- Hoya obovata – This Hoya has very dark green, round, lightly speckled leaves. Compared to many Hoyas, this one is relatively fast growing and flowers earlier than most
- Hoya keysii – The leaves are spade-shaped, soft to touch and slightly furry.
Care tips for your Hoya Carnosa:
- Provide bright indirect light. The plant will grow in lower light however requires bright indirect light year around to bloom. If you have too much light, your leaves may yellow or burn.
- Do not overwater. Soil must be allowed to dry out between waterings so choose well-draining, lightweight potting soil. Overwatering can cause leaves to drop.
- Wax plants love high humidity and therefore misting them, when not flowering, is advised
- Allow flowers to fade and fall naturally. Do not cut or pinch off the short flower stems, called spurs or peduncles, as new flower buds develop on old spurs
- They like to be at least somewhat root bound. Don’t grow hoyas in huge pots.
Although Hoyas have some specific requirements when it comes to producing flowers, it is a simple plant to care for and quite forgiving if neglected. I recently took several cuttings from my plant and after about 3 weeks, each had successfully rooted. I’m now looking forward to growing more of these beauties and keeping the tradition of sharing them with generations to come.
