Last Updated on October 8, 2022 by Plant Mom Care
Hoya Pubicalyx is indigenous to the Philippines and is featured on the five-centavo coin of the Philippines. It is characterized by its green succulent lanceolate leaves and tiny pink star-shaped fragrant flowers and grows like a vine on other plants.
This plant produces Anthocyanin, a natural pigment that protects the young foliage from excessive light. Sometimes the foliage is decorated with gray specks and purple-gray stems.
Depending on the type of cultivar, it can take about 1-2 years to start flowering.
The tiny flowers thrive in clusters on flower shafts with each cluster containing about 40 flowers, with various other varieties of Hoya Pubicalyx featuring diverse colored flowers. The sweet fragrance of the flowers is more noticeable at night and is used to make perfumes, body lotions, powders, and various other aromatic beauty products.
Popularly grown as a houseplant in more temperate climates, many variegated forms can be found in nurseries. It can add beauty to any indoor space by growing it in hanging baskets or terrestrial pots. While it doesn’t need heavy maintenance, it is a faster grower than other Hoya varieties.
Hoya Pubicalyx Light Requirements
The plant thrives under bright indirect light so place it near a shaded sunny window. It can also grow in natural sunlight or under artificial lights but avoid growing them under direct sunlight if you plant them outdoors.
You can use a shade cloth to cover it outdoors to stop the sun from burning the leaves and flowers. It needs six hours of bright indirect light every day to produce flowers.
Hoya Pubicalyx Watering
While it is a drought-tolerant plant it needs to be watered thrice weekly during the growing season. Wait for 2 inches of the topsoil to dry before watering it again in fall and winter.
However, the more light it gets the more water it will need. Don’t allow it to sit in water – the leaves will start to drop if you overwater it if the leaves start to look wrinkled, the plant might need watering.
If it is growing in a peaty soil mix, then water it less often as the soil will retain water. On the contrary, it can be watered more often if it grows in a lighter well-draining mix.
Hoya Pubicalyx Humidity
This plant enjoys high humidity levels of 60% to 70% indoors or outdoors. If you live in an arid climate, placing the plant close to a humidifier regular misting can also help; however don’t mist the plant when it starts flowering.
Protect the plant from cool air-conditioning vents and warm heaters to prevent the foliage from becoming dry.
Hoya Pubicalyx Temperature
It thrives in temperatures ranging from 60 – 75°F. It cannot tolerate cold or frost so temperatures below 50°F will damage or even kill the plant.
Hoya Pubicalyx Soil
It prefers light, well-draining soil that helps prevent root rot. To get the best outcome prepare a soil mix of equal parts of orchid bark, compost, and coarse sand or perlite.
You can also use a cactus soil mix, but it will have to be amended with some perlite to drain well. Maintain an acidic to neutral soil pH of 6.5 to 7.5.
Hoya Pubicalyx Repotting
It’s best to repot this plant in spring or early summer. This plant prefers to be root-bound so use a pot that is just a little bit larger. Depending on its growth rate repotting can be done every 5 years or so, as long as the plant is healthy and the soil drains well.
Hoya Pubicalyx Propagation
This plant is propagated from stem cuttings, with spring and summer being the most suitable time for this. Note: some gardeners recommend taking cuttings at the beginning of spring as this allows them to root early.
Sterilize your pruning shears with alcohol and take several 6 – 7” cuttings from a growing stalk. Remove the leaves at the bottom and place the cutting aside under shade to let the cuts callus and dry for a while.
Now plant the cuttings with the nodes under the soil about 4” deep. Keep the cuttings in a humid and warm spot under indirect light.
Water them about thrice a week until new growth is visible. Reduce watering but keep the soil lightly moistened. Rooting can take about 4 weeks to set.
After rooting sets, the cutting can be repotted and placed in a shaded sunny location to protect the leaves from getting burned.
You could also place the cuttings in plastic bags along with suitable soil and sphagnum moss until the cuttings root.
This plant is not a heavy feeder, although it will appreciate added nutrition during spring and summer. A diluted liquid fertilizer with a high potassium content is recommended; you could also spray it with foliar fertilizer. Some recommend using a monthly application of compost tea to not feed the plant in winter as it becomes semi-dormant. Make sure the soil is damp before feeding to avoid root burn.
This plant needs little or no pruning, except when growth becomes too unruly for your taste or to remove yellow leaves or damaged stems prune it in spring after it flowers. When pruning, remember to save some parts to propagate new plants. Also, don’t forget to use gloves as the white sap produced can irritate the skin.
Hoya Pubicalyx Common Problems
You usually might not have to deal with pests if the plant is healthy and well-cared for, however pests like fungus gnats, mealybugs, aphids, and root-knot nematodes often find ways to attack the plant anyway.
Fungus gnats thrive in humidity and the best prevention is to ensure the soil drains well as they like to lay eggs in wet soil. They won’t do that if the topsoil is dry as the larvae don’t like that. If they do succeed, remove 2 inches of topsoil and control them with insecticidal soap or neem oil.
Mealybugs are attracted to the warmth and moisture the plant thrives in, making it more susceptible.
They will suck the sap and damage the plant and have to be treated fast. As they are small, it’s difficult to see them spot them and the only signs will be leaves turning yellow or shriveling. Use a strong water spray, neem oil, insecticidal soap, or alcohol to eliminate them.
Aphids are usually found under the leaves and look like minute yellow, brown or black dots. They make the leaves turn yellow or curl up. Use a strong water spray, neem oil, or insecticidal soap. Repeat every 3 days for 2 weeks.
The most destructive pests are root-knot nematodes as they damage the roots and are difficult to detect. The only indication of damage is the plant slowly declining until it dies. One nematode lays almost 1,000 eggs and can infest the entire root ball. If you suspect the roots are affected, dig the plant out and inspect the roots – signs of infection are indicated by large knots on the roots.
Your only option is to take healthy cuttings and propagate them as treating the soil and removing infected roots seldom works. Insecticides to kill the pests will kill the plant as well.
Generally, a lack of flowers indicates that the plant isn’t getting sufficient light. Make sure the plant gets lots of bright indirect light.
Red or dried leaves are a sign of too much direct sun burning the leaves. Move the plant to a better location.
Shriveled or yellow leaves could indicate infestation by aphids, mealybugs, under-watering or low humidity. Check your watering frequency and humidity levels and inspect the plant for pests to identify the problem.
If the plant looks droopy or unhealthy, over- or under-watering or pest infestation might be the problem. Check your watering frequency and inspect the roots for pests to identify the problem.
If leaves start falling off the plant, this usually indicates that the plant is exposed to cold or is in a drafty spot, move it to a more suitable location.
What is the difference between Hoya Carnosa and Hoya Pubicalyx?
Both these varieties look similar with some differences in their leaves. The leaves of Hoya Carnosas are wider, shorter, and thicker while those of the Hoya Pubicalyx are thinner and longer and also have gray speckles. The Carnosa leaves are either green or variegated.
How many types of Hoya Pubicalyx are there?
While the Hoya genus contains 600 to 700 varieties, the most common and popular Hoya Pubicalyx varieties are Black Dragon, White Dragon, Pink Dragon, Pink Silver, Royal Hawaiian Purple, Red Buttons, Bright One, Silver Sheen, Dapple Gray, Splash, Jungle Garden and many other hybrids.
Is Hoya Pubicalyx a fast grower?
Hoya Pubicalyx grows faster than other varieties in the genus. Outside of its native habitat, this plant can grow to a mature length of 8 – 10 feet. In the Philippines, it can grow to around 20 feet.