Origin and Habitat: Garden origin. The natural species comes from the Philippines.

• Hoya pubicalyx cv. Royal Hawaiian Purple
• Hoya pubicalyx cv. Chimera

• Hoya pubicalyx cv. Red Button
• Hoya pubicalyx cv. Royal Hawaiian Purple
• Hoya pubicalyx cv. Chimera

Description: Hoya pubicalyx cv. Royal Hawaiian Purple is a fast growing cultivar suited for baskets or ladders. It has pretty neat flowers. Flowers about 10 mm across comes in bunches of 20 to 40 hanging from along the stems. Bunches may be over 10 cm across. You can see clusters with pink-red flowers and also on the same plant you might see clusters that are almost black. Some of the clusters are even mixed pink-re and black. This is a very attractive hoya. The narrow 10 cm long leaves show some silvery-grey flecking patterns. Another good thing about H. pubicalyx is that they are some of the more cold hardy hoyas. They can even take frost for a short period of time.
Similar cultivars: This cultivar is very similar and often confounded with Hoya pubicalyx cv. Red Button, but it has narrower leaves than 'Red Button' and also more flecks. This hoya is also known under the name 'Chimera', but 'Royal Hawaiian Purple' is the correct name. It's a nice hoya that gets pink/red new leaves in the sun.

Cultivation and Propagation: Hoya pubicalyx is a Philippine species that is not only easy to grow but quite floriferous. It is an excellent plant for house culture as it stands the extremes of heat and cold better than most plants, and is not easily injured by neglect it can be trained to climb on trellis-work to almost any height, and when in bloom, which continues for half the year, it is a very interesting plant. People often just let them go about their business, trailing around the perimeter of a windowsill and even through-out the house. Some also let them trait out of a hanging pot with their thick waxy leaves looking quite orderly. There are a few Hoya's which make ideal houseplants, Hoya pubicalyx is one of them. It can also handle some cold temps if absolutely dry and does well in just about any light level.
Growth rate: Although the vines can reach lengths of 6 m in the wild, cultivated plants generally extend 1,5-2 m, twisting around supports to which they cling or hanging down in attractive cascades from suspended pots. The all green variety tends to grow more quickly (although it's still slow by most houseplant standards) and is arguably more hardy, but it also comes in a some pretty slow growing variegated varieties.
Potting medium: Bacuse it is an epiphyte benefits from being potted up in a very well-draining and porous potting medium that allows some air to get to the roots; typical mixes include, peat, with some fibrous soil and sand along with large-grade drainage material such as perlite, pumice, or ceramic balls. Often specialized hoya growers either use only chopped coconut husk or a good orchid potting mixture for growing their hoya plants. The medium needs to be moisture-retentive.
Fertilization: The plants should be fed regularly with a fertilizer suitable for epiphytic plants.
Watering: With its succulent qualities it's quite adapt at storing water for longish periods of time between waterings. Water regularly in summer, but do not overwater (wet-sensitively) and let the plants to dry out between watering and then water again. Its roots are easily lost in pots that stay damp for any length of time. Keep quite dry with ample airflow in winter (It would probably tolerate one watering a month). In the rest period no high atmospheric humidity. Care must be taken with watering as they tends to become swollen and untidy in growth habit if given too much water and shade.
Fertilization: During the growing season enrich the soil using a fertilizer rich in potassium and phosphorous, but poor in nitrogen, because this chemical element doesn’t help the development of succulent plants, making them too soft and full of water.
Exposition: This hoya species prefers bright light, but will tolerate much less. Outside half shade to shade (filtered sunlight or afternoon shade tolerated) , inside it will need a reasonably light room in order to actually grow, although it will still get by even in a shadier spot and can be positioned almost anywhere in homes or offices. It subject to sunburn if exposed to direct sun for too long. Tends to bronze in strong light, which encourages flowering and heavy leaves production.
Hardiness: The optimal temperature is 16-30°C (USDA Zones: 10 -12 ), but can handle some cold temps if absolutely dry and does well in just about any light level.
Spring: When winter ends and they begin to grow again, they will require much water and soaking the pots will no longer put the plants at risk for rot. In the spring they will grow well in partial shade and leaving them out in the rain may provide them with the water they need.
Summer: In the summer months they will tolerate heavy rain, but will be just as happy if the season is dry. They will tolerate hot weather outdoors as long as they are kept in strongly filtered light and this will encourage them to flower. They also enjoy some fertiliser. Moving the plants as they are developing buds may cause them to spontaneously abort the flowers all together.
Autumn: In the fall keep them outdoors until the night time temperatures drop below the 10°C.
Winter: Winter care presents no problems at 10° C with plenty of light. In winter be sure to take extra precautions to keep them dry, because damp cool conditions when the plants are resting is an invitation to fungal infections, but - according to temperatures –some occasional lit watering may be useful.
Maintenance: Prune the plant lightly to keep it tidy.
Repotting: In any season it's best to lay the stems out for several days before replanting them and then pot them only in dry soil and withhold any water until they begin to shrivel or start growing again. Re-pot every 2 years.
Pest and diseases: Hoyas are generally fairly easy to grow, especially if kept pest-free. They are very susceptible to stem and root mealy bugs, and damage from these may well initiate fungal attack. Any time when there is a dead or dying stem in the pot it is important to remove it immediately and completely before other healthy stems can become ill too, isolate the healthy parts, dry them off, and re-root them in new compost.
Propagation: It is easily propagated from cuttings. The stems produce aerial roots which roots easily when inserted into a moist medium making it easy to propagate new plants from stem cuttings. Allow cuttings to dry a day before planting. A very good method is to wrap a cutting in moss, keeping it moist until the roots are well started. It can also be increased from seeds sowing in spring in moist, sandy peat moss. Barely cover seeds. Seeds germinate quickly.