Hoya is a genus of more than 550 climbing epiphytes from tropical and subtropical Asia and the western Pacific, according to NC State Extension. They are grown for thick, waxy leaves and umbels of star-shaped flowers, many of them fragrant. Most species are easy to grow. They differ in leaf shape and colour, in how fast they grow, and in how readily they flower indoors.
14 hoya varieties at a glance
Descriptions are from NC State Extension species and cultivar profiles.
| Hoya | Leaves | Flowers | Growth and difficulty |
|---|---|---|---|
| H. carnosa (wax plant) | Thick, waxy, green | Star-shaped, pink or white, fragrant, red centre | Rapid climber; the standard beginner hoya |
| H. carnosa ‘Krimson Queen’ (‘Tricolor’) | Green centre, cream to pink margins | As H. carnosa | As H. carnosa |
| H. carnosa ‘Krimson Princess’ | Pink and white variegation, dark green margins | As H. carnosa | As H. carnosa |
| H. carnosa ‘Compacta’ (‘Krinkle Kurl’, Hindu rope) | Folded over into a rope-like stem | As H. carnosa | Rope-like trailing stems |
| H. kerrii (sweetheart hoya) | Thick, heart-shaped | Small, pink with red centre, fragrant at night | Slow |
| H. pubicalyx | Long, narrow, glossy dark green; silvery-pink in sun; ‘Splash’ is speckled | Clusters of pink stars | Rapid |
| H. australis (common hoya) | Bright green, rounded | White with red centre, very fragrant | Grows quickly and flowers sooner than other hoyas |
| H. bella (beautiful hoya) | Small, glossy, lance-shaped | White stars with pinkish-purple corona | Slow; trails 30–60 cm (1–2 ft) |
| H. lacunosa (cinnamon hoya) | Deep green, pitted | Fuzzy white with yellow corona, cinnamon-scented at night | Rapid; compact creeping vine |
| H. curtisii | Tiny, round, olive green mottled with grey | — | Miniature trailer |
| H. obovata | Large, deep green oval with silver splash | Pink and white clusters | Less common |
| H. wayetii | Lance-shaped, dark green with light green to cream margins | Small red to burgundy stars | — |
| H. retusa | Thin, grass-like | White with red centre | Trailing |
| H. linearis | Slender, fleshy, linear, on trailing stems | Fragrant white stars | NC State calls it hard to grow |
NC State also lists H. shepherdii (string bean hoya, long thin succulent leaves) and the rare H. kentiana.
Hoya carnosa and its cultivars
Hoya carnosa is native to Southeast Asia, Japan and Taiwan. The species name means “fleshy”, for its succulent leaves. NC State describes it as a rapid climber suited to hanging baskets. Its cultivars differ in leaf colour or shape:
- ‘Krimson Queen’ (also sold as ‘Tricolor’): green centre ringed with creamy white to pink.
- ‘Krimson Princess’: the reverse, with pink and white variegation in the centre and dark green margins.
- ‘Variegata’: creamy-white margins, sometimes tinged pink.
- ‘Compacta’ (‘Krinkle Kurl’, Hindu rope plant): leaves folded over into a rope-like look.
Variegated cultivars have less green tissue and do best at the brighter end of a hoya’s range.
Sweetheart hoya (Hoya kerrii)
Sold around Valentine’s Day as a single heart-shaped leaf in a pot. NC State warns these single rooted leaves are not likely to grow well unless some stem tissue came with the leaf. Buy a cutting with a stem if you want a vine.
H. kerrii grows slowly. NC State recommends:
- Temperature: 18–27 °C (65–80 °F).
- Humidity: a humid room such as a kitchen or bathroom.
- Water: room-temperature water, since cold water can shock it.
- Pruning: do not cut back the long, bare twining stems. New leaves and flowers form on them.
‘Variegata’ has a green centre and a creamy white border.
Hoya pubicalyx
A fast-growing climber from the Philippines with long, narrow, glossy leaves that turn silvery-pink in sun. NC State gives it more specific requirements than most hoyas:
- Light: about six hours of filtered sun a day, with no more than two hours of direct morning sun.
- Temperature: above 10 °C (50 °F).
- Humidity: 60–70%.
- Pot: terracotta or another well-drained pot. It rarely needs repotting.
- Water: filtered water or rainwater.
Hoya australis
Native from Borneo to New Guinea and Australia. NC State notes it grows quickly as a houseplant and produces flowers sooner than other hoyas. That makes it the best choice if flowers are the point. Keep it pot-bound in well-drained soil, in bright light, and do not overwater. ‘Lisa’ has pinkish new leaves that mature to green mottled with cream.
Small and trailing hoyas: bella, lacunosa and curtisii
Hoya bella is a small, cascading vine from Assam and Myanmar that trails 30–60 cm (1–2 ft). It grows slowly and likes 24–29 °C (75–85 °F) with 50–60% humidity. Let the mix become almost dry before watering. NC State advises not moving or even rotating the pot once flower buds appear, and notes leaf drop can follow sudden changes in temperature or light.
Hoya lacunosa (cinnamon hoya) is a compact, fast-growing creeper from Myanmar and Malaysia with pitted leaves. Its umbels carry up to 30 fuzzy white flowers that smell of cinnamon, especially at night. NC State recommends an orchid mix, or perlite, pine bark, sand and peat. Cultivars include ‘Royal Flush’ (red-edged leaves, pink flowers), ‘Snowcaps’ (white-speckled leaves), ‘Splash’, ‘Mint’, ‘Silver’, ‘Eskimo’ and ‘Black Queen’.
Hoya curtisii is a miniature trailer with tiny round leaves mottled grey, suited to small hanging pots.
Getting any hoya to flower
- Give more light. University of Missouri Extension says hoyas tolerate low light but need medium light to grow and high light to flower. NC State recommends bright light, dappled shade or full morning sun, but not full sun all day.
- Be patient. NC State says most H. carnosa plants do not flower until they are 2 or 3 years old.
- Leave the spurs. Flowers form on short stalks (peduncles). These rebloom for years, so cutting them off removes future flowers.
- Keep it snug. Hoyas tolerate being pot-bound. When you do repot, NC State recommends going up no more than 5 cm (2 in), and not while the plant is in bud or flower.
- Do not move a budding plant, particularly H. bella.
Care that applies to every hoya
From NC State Extension:
- Mix: loose, fast-draining and high in organic matter. As epiphytes, hoyas do not tolerate soggy mix or wet roots.
- Water: let the mix dry between waterings. Both too wet and too dry can cause leaf drop.
- Support: they grow better trained on a trellis or pole, or trailing from a hanging basket.
- Pests: mealybugs; fungus gnats in mixes kept too wet; spider mites when the air is too dry.
- Temperature: frost-intolerant. Bring summering plants indoors when nights fall below 10 °C (50 °F).
See our hoya care guide for watering and problem diagnosis, and the hoya plant hub for common problems.
Pets
The ASPCA lists wax plant (Hoya carnosa), including ‘Krinkle Kurl’, as non-toxic to dogs and cats. Other Hoya species are not individually listed by the ASPCA. NC State notes H. lacunosa can cause contact dermatitis.
References
- NC State Extension Gardener Plant Toolbox: Hoya (genus), Hoya carnosa, Hoya kerrii, Hoya pubicalyx, Hoya australis, Hoya bella, Hoya lacunosa
- University of Missouri Extension, D. H. Trinklein (rev. 2016): Lighting Indoor Houseplants, G6515
- ASPCA Animal Poison Control Center: Wax Plant