Hoya Carnosa (Hoya carnosa) is a houseplant worth getting to know properly, and this guide covers exactly how to keep it healthy: light, water, soil, humidity, temperature, feeding, repotting, propagation and the problems that show up when something is off. The care numbers below come from the plant data used for this guide.
Hoya Carnosa is a vigorous climber or trailer that will climb a trellis or cascade from a hanging basket, with thick, waxy, oval leaves with a glossy shine. The classic wax plant - thick, glossy leaves and, on a mature plant, clusters of star-shaped, pink-centred white flowers that smell sweetly in the evening. Once you understand what it wants - and, just as importantly, what it does not want - it is a straightforward plant to keep looking good for years.
Hoya Carnosa at a glance
| Care factor | What this plant needs |
|---|---|
| Botanical name | Hoya carnosa |
| Light | bright indirect |
| Water | every 1–2 weeks; let soil dry between waterings |
| Humidity | moderate |
| Temperature | 60–85°F (16–29°C) |
| Repotting | every 2–3 years |
| Pet safety | non-toxic to cats and dogs |
Light
Give your hoya carnosa bright indirect light. A spot near an east- or west-facing window is usually ideal, and a little gentle morning sun is welcome - it encourages flowering. Harsh midday sun through a south-facing window can scorch the leaves, while too little light gives leggy growth and no flowers at all. Flowering is the best test of your light: a hoya that grows but never blooms is almost always asking for more light. Our grow-light calculator can work out how many hours your plant needs.
Watering
Water every 1–2 weeks; let soil dry between waterings. Push a finger into the mix before you water: if it is still damp, wait; if it is dry, water thoroughly until water runs out of the drainage holes, then let the excess drain away completely and empty the saucer. Hoyas store water in their thick, waxy leaves, so they forgive a missed watering far more easily than a soggy pot - root rot in a heavy, wet mix is the most common way to lose one. Water less in winter, when growth slows. Our watering calculator can help you work out a starting routine for your pot size, and the watering schedule generator can turn it into a plan you can follow.
Humidity and temperature
Hoya Carnosa prefers moderate humidity and temperatures of 60–85°F (16–29°C). Most homes sit within that temperature range for most of the year, so temperature is rarely a problem indoors - the things to watch are cold draughts in winter, radiators that dry the air, and cold windows that chill the leaves overnight. Keep the plant away from all three. In a heated home in winter the air can be much drier than this plant likes, and the first sign is usually brown, crispy leaf edges or tips. A pebble tray under the pot, grouping plants together, or a small humidifier all raise the humidity around the plant. Misting does very little - the water evaporates in minutes. Our humidity and temperature checker can tell you whether your room suits this plant.
Soil and potting
Use a very chunky, airy mix with bark and perlite, much like an orchid mix. Ordinary potting soil holds too much water for a hoya and compacts around the roots, so mix bark and perlite into good potting soil, or use a ready-made orchid mix with a little soil added. A pot with drainage holes is not optional, and hoyas actually flower best when slightly pot-bound, so do not rush to give it a bigger home. Our potting-mix calculator can work out the parts for a homemade mix for your pot size.
Repotting
Repot every 2–3 years, or sooner if roots are circling out of the drainage holes or pushing out of the top of the pot. Move up only one pot size - a pot that is too big holds wet mix the roots cannot use - and repot in spring, when the plant is about to grow. Fresh mix gives the roots a new supply of air and nutrients. Our repotting calculator can help you work out the next pot size and how much fresh mix you will need.
Feeding
Feed during the growing season, in spring and summer, with a balanced liquid houseplant fertiliser at half strength, and do not feed in autumn and winter when the plant is barely growing. A little extra feeding in the months before flowering can help, but always follow the label - excess salts burn the roots and show up as brown leaf tips. Flush the mix with plain water every few months to wash salts out.
Propagation
Hoya Carnosa is propagated by stem cuttings. Take a stem cutting with at least two nodes in spring and root it in water, moist sphagnum moss or a chunky mix. Keep it warm and bright, and roots form within a few weeks. Never cut off the flower stalk (peduncle) after blooming - new flowers grow from the same stalk.
Common problems and fixes
| Problem | Likely cause | Fix |
|---|---|---|
| Wrinkled leaves | underwatering | Water thoroughly and let the plant soak up what it needs. Wrinkled, soft leaves are the plant using up its stored water - they usually plump up again within a day or two of watering. |
| Brown leaf edges | low humidity | Raise the humidity around the plant - group it with other plants, use a pebble tray or run a humidifier - and flush the soil with plain water to wash out salts. |
| No flowers | plant too young or too little light | Move the plant to brighter light and be patient - a young plant may need a year or two before it flowers, and a plant that is too comfortable in low light will grow leaves and skip blooming. |
Wrinkled leaves
Likely cause: underwatering. Water thoroughly and let the plant soak up what it needs. Wrinkled, soft leaves are the plant using up its stored water - they usually plump up again within a day or two of watering.
Brown leaf edges
Likely cause: low humidity. Raise the humidity around the plant - group it with other plants, use a pebble tray or run a humidifier - and flush the soil with plain water to wash out salts.
No flowers
Likely cause: plant too young or too little light. Move the plant to brighter light and be patient - a young plant may need a year or two before it flowers, and a plant that is too comfortable in low light will grow leaves and skip blooming.
Frequently asked questions
How often should I water hoya carnosa?
Water every 1–2 weeks; let soil dry between waterings. Always check the soil with a finger first rather than watering on a fixed day, because the interval changes with the season and pot size. Water thoroughly when it is time and let the excess drain away completely.
How much light does hoya carnosa need?
It needs bright indirect light. A spot near an east- or west-facing window usually suits it well. Too little light gives weak, stretched growth, while harsh midday sun can scorch the leaves.
Is hoya carnosa safe for cats and dogs?
According to the data used for this guide, hoya carnosa is non-toxic to cats and dogs, which makes it a good choice for homes with pets. It is still best not to let pets chew it, as any plant material can upset a stomach.
When should I repot hoya carnosa?
Repot every 2–3 years, or sooner if roots are circling out of the drainage holes. Move up only one pot size, use fresh mix, and repot in spring.
Why is my hoya carnosa not flowering?
Mature plants produce round clusters of waxy, star-shaped flowers, white with a pink centre, that are sweetly scented, especially in the evening. Flowering needs bright light and a plant that is a little pot-bound. The most common reason for no flowers is too little light - move the plant to a brighter spot and give it time.
Related guides
Browse the full houseplants hub for more species care guides, and try the tools hub for calculators that help with watering, light and repotting.