# Hoya (Hoya carnosa)

Canonical: https://plantguide.ae/plants/hoya · Updated: 2026-10-07
Source: Plant Guide (https://plantguide.ae/plants/hoya)

Hoya · also called Wax plant, Porcelain flower, Sweetheart hoya (Hoya kerrii)  
indoor · exotic · family Apocynaceae · grows 0.3–1.5 m tall, 0.2–0.6 m wide · moderate growth  
part shade · moderate water need  
Ratings for Dubai (1–5, 5 is best): heat 1 · salt 1 · drought 3 · shade 2 · ease of care 3  
Sow or plant: Feb–Apr, Oct–Nov  
Uses: indoor, container, climber

A trailing wax plant with thick, glossy leaves and clusters of star-shaped flowers when it gets bright light. Non-toxic to cats and dogs per the ASPCA, but it dislikes dry AC air and drops buds if moved.

## About

Meet hoya, the wax plant: thick, glossy leaves on long, trailing stems and, once it is happy, clusters of small, waxy, star-shaped flowers. NC State describes the blooms as white to pink and hairy in the centre, up to 30 in a cluster, and says most plants flower at two to three years old.

It is an epiphyte from Southeast Asia, Japan and Taiwan (NC State), a plant that grows on trees in the wild. That explains why it wants a loose, fast-draining mix, does not mind a snug pot, and prefers its roots barely moist. It also explains why it dislikes dry air and wet feet at the same time.

There is a pet-safety bonus. The ASPCA lists both the sweetheart hoya (Hoya kerrii) and a Hoya carnosa cultivar as non-toxic to cats and dogs, which makes it one of the few trailing plants you can hang near a cat, though the ASPCA notes that eating any plant can still upset a stomach.

Hoya carnosa is a vining epiphyte in the dogbane family, Apocynaceae, from Southeast Asia, Japan and Taiwan. NC State describes rapid growth, thick leaves that suit a hanging basket, and clusters of up to 30 star-shaped flowers. Hoya kerrii, the sweetheart hoya, is the other one shops sell, and cultivars such as 'Crimson Queen' are on sale in Dubai.

It wants bright light without hot sun. NC State calls bright, indirect light year-round ideal and says it tolerates two to six hours of direct sun; the RHS says to keep it out of hot sun in summer, and that too little light is why a hoya fails to flower. Behind tinted glass, sit it right by the window and watch the leaves: a plant that grows but never flowers is asking for more light.

Water when the top of the mix has dried, using room-temperature water. NC State says both too-wet and too-dry soil make the leaves drop. The RHS says to keep the compost moist but not waterlogged from spring to autumn, then let it dry somewhat between waterings from October to February. Hoyas dislike dry air (RHS), and NC State lists mealybugs, fungus gnats from wet soil and spider mites from dry air as the usual pests.

Do not cut off the flower stalks. NC State says the stalk, or spur, flowers again for several years if left alone, and the RHS says never to move a plant with formed buds, which may drop. A hoya does not mind being pot-bound (NC State); repot only when roots fill the pot and it is not in bud, into a pot no more than 5 centimetres wider.

## Indoors in Dubai

- **Light:** grows well in bright indirect light. Bright light without hot sun: by an east window, or about a metre from tinted south or west glass. Too little light means no flowers (RHS); hot summer sun through glass scorches the leaves.
- **Dry air and air conditioning:** tolerance 3 out of 5 (1 = needs humidity help, 5 = indifferent). Dry air brings spider mites (NC State). Keep it out of the vent airflow, stand it on a saucer of damp pebbles, and do not move it once buds form, because the RHS says they drop.
- **Pets:** pet-safe: not toxic to cats or dogs on the ASPCA list.
- **Size:** tabletop.
- **Rooms:** living room, bedroom, home office, kitchen.
- **Finding it in Dubai:** specialist: look in specialist plant shops and larger garden centres.
- **Outdoors:** never: keep it indoors all year.

## Through the year

Hoya keeps its leaves all year, and its calendar is set by light, flowers and water. NC State has it flowering in spring, summer or autumn, so look for buds in the brighter months and leave the plant where it is once they form. The RHS's growing season runs from spring to autumn, when the compost should stay moist but not waterlogged and the plant gets regular feeding. In June to September keep it back from hot glass and out of the AC airflow. From October to February the RHS says to water less, letting the compost dry somewhat between drinks but never completely.

| When | What | Note |
| --- | --- | --- |
| Feb–Apr, Oct–Nov | Plant: Buy and pot up | The RHS repots in spring, only when roots fill the pot, and never while the plant is in bud. |
| Mar–Oct | New growth: Growing season | Keep the compost moist but not waterlogged (RHS). |
| Apr–Oct | Flowers: Star-shaped flower clusters | NC State gives spring, summer or autumn; leave the flower stalks in place. |
| Mar–Sep | Feed: Regular feed | The RHS says every two weeks in spring and summer with a balanced feed, monthly in autumn and winter. |
| Apr–Sep | Pest watch: Mealybugs and spider mites | Dry air brings mites; wet soil brings fungus gnats. |
| Jun–Sep | Heat stress: Hot glass and dry air | Keep it out of hot summer sun (RHS) and raise humidity with a damp-pebble saucer. |
| Oct–Feb | Dormant: Water less | The RHS says to let the compost dry somewhat between waterings, but never completely. |

## Care in Dubai

- **Watering in summer:** Water when the top of the mix has dried, using room-temperature water (NC State). The RHS says to keep the compost moist but not waterlogged from spring to autumn. Test two inches down rather than following a calendar, and flush the pot every four to six months to clear salts (University of Maryland).
- **Watering in winter:** From October to February the RHS says to water less, letting the mix dry somewhat between drinks but never completely.
- **Soil:** A loose, fast-draining mix high in organic matter (NC State). The RHS suggests equal parts orchid bark, peat-free multipurpose compost and coarse perlite.
- **Feeding:** The RHS suggests a balanced orchid fertiliser every two weeks in spring and summer and monthly in autumn and winter, flushing the pot with plain water now and then, and skipping feed for five to six weeks after repotting.
- **Pruning:** Do not cut off the flower stalks: NC State says the same spur flowers again for years. Trim only long, bare stems, and root the cuttings.
- **Planting:** Use a pot with drainage holes. A hoya does not mind being pot-bound; repot in spring only when roots fill the pot and it is not in bud, into a pot no more than 5 centimetres wider (NC State, RHS).
- **Pests and problems:** Mealybugs; Spider mites; Fungus gnats; Scale insects
- **Toxicity:** Non-toxic to dogs and cats, according to the ASPCA, which lists the sweetheart hoya (Hoya kerrii) and the wax plant (Hoya carnosa 'Krinkle Kurl'). NC State lists H. carnosa as non-toxic to cats, dogs and horses. The ASPCA adds that eating any plant material can cause vomiting and stomach upset, even for non-toxic plants.

## Good and bad

**Pros**
- Non-toxic to cats and dogs per the ASPCA (H. kerrii and a H. carnosa type)
- Thick, waxy leaves stay glossy all year
- Flowers again from the same stalks for years when light is good (NC State)
- Does not mind being pot-bound, so repotting is rarely needed
- Trails from a shelf or basket and roots from stem cuttings

**Cons**
- Fails to flower in dim rooms; the RHS says too little light is the cause
- Dislikes dry air, and spider mites follow in AC rooms
- Drops buds if moved, and leaves if the soil swings from wet to dry
- Slow to bloom: most plants flower at two to three years old (NC State)

## Common mistakes

- Moving it once buds form. The RHS warns that buds may drop, so pick the spot and leave it.
- Cutting off the flower stalks after the flowers fade. NC State says the same spur flowers again for several years.
- Keeping it in a dim corner. The RHS says too little light is why a hoya does not flower; bright, indirect light is the goal.
- Overwatering, or letting it swing from soaked to bone dry. NC State says both extremes make the leaves drop.
- Moving it into a big pot. It does not mind being pot-bound, and a pot more than 5 centimetres wider holds wet mix around the roots.

## Good to know

- The ASPCA lists sweetheart hoya (Hoya kerrii) and a wax plant cultivar (Hoya carnosa 'Krinkle Kurl') as non-toxic to dogs and cats, and NC State lists H. carnosa as non-toxic to cats, dogs and horses. The ASPCA still says eating any plant material can cause vomiting and stomach upset.
- NC State says most plants flower at two to three years old, so a young plant that has not flowered is not failing.
- Hoyas are sold under cultivar names such as 'Crimson Queen', so check the label for the light and watering each one wants.
- Prices seen on 7 October 2026: Adplants lists a small 'Crimson Queen' hoya (10 to 15 cm) at AED 30.

## Using it in a garden

Roles: Hanging basket, Shelf trailer, Bright windowsill plant, Pet-friendlier trailer (ASPCA)

Hoya earns the brightest corner of a room that never gets hot direct sun: beside an east window, or a metre or so from a tinted south or west window. Let it trail from a shelf, hang it in a basket, or train it up a small trellis or hoop. Keep it out of the vent airflow, stand it on a saucer of damp pebbles for a little extra humidity, and once buds appear leave it exactly where it is.

- [Pothos](https://plantguide.ae/plants/pothos.md): Pothos covers the dimmer end of the same shelf with thin, fast trailing stems against hoya's thick, waxy ones; pothos is toxic to pets, so keep it out of reach if you pair them.
- [Peperomia](https://plantguide.ae/plants/peperomia.md): Peperomia's compact, rounded leaves make a tidy low mound under a trailing hoya, with a similar need for bright light and a drier mix.
- [Snake plant](https://plantguide.ae/plants/snake-plant.md): Snake plant's stiff, upright blades contrast with hoya's trailing stems on a bright shelf or sideboard.

## FAQ

**Why is my hoya not flowering?**  
Too little light is the usual reason (RHS). Move it to bright, indirect light, and be patient: NC State says most plants flower at two to three years old. Do not cut the old flower stalks; they flower again.

**How often should I water a hoya in an air-conditioned room?**  
When the top of the mix has dried, not by the calendar. NC State says too-wet or too-dry soil makes the leaves drop, and the RHS says to water less from October to February.

**Is hoya safe for cats and dogs?**  
The ASPCA lists the sweetheart hoya and a wax plant cultivar as non-toxic to both. Any plant can still upset a stomach, so discourage chewing.

**Does hoya need humidity?**  
NC State says it loves high humidity, and the RHS says it dislikes dry conditions. A saucer of damp pebbles helps locally; University of Nebraska Extension says misting is not effective, while a pebble tray helps locally and a humidifier raises humidity for a whole room. Keep it out of the vent airflow.

**Can I move a hoya that has buds?**  
Avoid it. The RHS says plants with formed buds may drop them if moved.

**Where can I buy a hoya in Dubai, and when?**  
Specialist and online plant shops stock them; Adplants listed 'Crimson Queen' at AED 30 for a 10 to 15 cm plant on 7 October 2026. Buy in October to November or February to April, when a plant is not carried home through summer heat.

## Related plants

[Pothos](https://plantguide.ae/plants/pothos.md) · [Peperomia](https://plantguide.ae/plants/peperomia.md) · [String of pearls](https://plantguide.ae/plants/string-of-pearls.md) · [Philodendron](https://plantguide.ae/plants/philodendron.md)

## Photos

![Hoya Carnosa](https://upload.wikimedia.org/wikipedia/commons/e/ea/NKN-2007-06-13_114250_Hoya_Carnosa_%28Yvan_Leduc_author_for_Wikipedia%29.jpg)  
Photo: Yvan leduc / CC BY-SA 3.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:NKN-2007-06-13_114250_Hoya_Carnosa_(Yvan_Leduc_author_for_Wikipedia).jpg))

![Hoya carnosa - umbel with nectar droplets](https://upload.wikimedia.org/wikipedia/commons/f/f4/Hoya_carnosa_-_umbel_with_nectar_droplets.jpg)  
Photo: Franz van Duns / CC BY-SA 4.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Hoya_carnosa_-_umbel_with_nectar_droplets.jpg))

![Hoya (Hoya carnosa), inflorescence, in a garden, France..](https://upload.wikimedia.org/wikipedia/commons/9/93/Hoya_FR_2013.jpg)  
Photo: JLPC / CC BY-SA 3.0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Hoya_FR_2013.jpg))

![Young wax vine flower buds that have not opened Closed buds (not yet open) or inflorescence of Hoya Carnosa](https://upload.wikimedia.org/wikipedia/commons/1/16/Closed_buds_%28not_yet_open%29_Inflorescence_of_Hoya_Carnosa.jpg)  
Photo: Muldoonsamuel / CC0 / Wikimedia Commons ([source](https://commons.wikimedia.org/wiki/File:Closed_buds_(not_yet_open)_Inflorescence_of_Hoya_Carnosa.jpg))

## Sources

- [NC State Extension Gardener Plant Toolbox: Hoya carnosa](https://plants.ces.ncsu.edu/plants/hoya-carnosa/)
- [RHS: How to grow hoya, growing guide](https://www.rhs.org.uk/plants/hoya/growing-guide)
- [ASPCA: Toxic and Non-Toxic Plants, Sweetheart Hoya](https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/sweetheart-hoya)
- [ASPCA: Toxic and Non-Toxic Plants, Wax Plant](https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/wax-plant)
- [University of Nebraska-Lincoln Extension: Houseplant humidity](https://lancaster.unl.edu/houseplants-humidity)
- [University of Maryland Extension: Watering indoor plants](https://extension.umd.edu/resource/watering-indoor-plants)
- [Adplants: pet-safe collection (price checked 7 October 2026)](https://adplants.com/collections/pet-safe)