Hoya’s are native to tropical forests and have specifically adapted to growing in high humidity with bright light and well-draining soil.
The most common reason for a hoya dying is because of overwatering and poor drainage. Hoyas grow as epiphytes on other trees and therefore require a well-draining, aerated potting medium to prevent root rot. Overwatering causes the hoya’s leaves to turn yellow and drop off.
Whilst overwatering and poor drainage are the most common reasons for a hoya dying, here is a table summarizing other reasons for a dying hoya houseplant:
|Symptoms of a dying Hoya Plant:||Reasons for a Dying Hoya:|
|Hoya Leaves Turning Yellow, Dropping Off and Dying:||The most common reasons are overwatering and compacted potting soil. Other reasons include nutrient-deficient soil, not enough water, or too much or too little sunlight.|
|Hoya Losing its Leaves:||Cold temperatures, not enough light, draughts from air conditioning or indoor heating. Too much or not enough water can also cause dropping leaves.|
|Hoya Leaves and Stems Becoming Wrinkled:||Some wrinkling on the leaves indicates slight drought stress probably due to low humidity and underwatering, although watering too often can also cause this.|
|Hoya Leaves Turning Brown and Dying:||Drought stress, due to a combination of low humidity, underwatering, too much sunlight, and high temperatures due to indoor heating.|
|Hoya Leaves and Stems Turning Brown and Black:||Brown or black stems can indicate fungal diseases that are caused by overwatering.|
|Hoya Not Growing:||Hoyas naturally more slowly than most houseplants but may grow even slower in areas of low light, cold temperatures, low humidity, a lack of fertilizer, or if it is pot-bound.|
To revive a dying hoya, it is essential to recreate some of the conditions of its native habitat with high humidity, bright indirect, warm temperatures and only watering when the top 2 inches of potting feel dry.
Keep reading for how to implement the solutions to save your dying hoya…
Hoya Leaves Turning Yellow and Dying
By far the most common cause of hoya leaves turning yellow (and falling off) is due to overwatering and compacted soils. Hoya plants sometimes grow as epiphytes which means they grow on other trees with the roots used to secure the plant to tree branches rather than in the soil on the forest floor.
Therefore hoya needs good drainage with aerated soil and should be watered less often than most houseplants.
The yellow leaves can develop brown spots and fall off which indicates fungal disease (which is caused by overwatering).
Other causes of yellow leaves include:
- A nutrient deficiency due to a lack of fertilizer (especially if the hoya has been in the same pot for too long as the roots can exhaust the soil of available nutrients).
- Too much or too little sunlight.
- Not enough water (if the soil has dried out too much then the roots cannot uptake nutrients, resulting in yellowing leaves).
Depending on how severe the stress is on your hoya the leaves may fall off. I find this is often the case with chronically overwatered hoyas.
The leaves of hoya can turn yellow or brown due to drought stress, with yellow leaves indicating that the hoya is not getting quite enough water (or you are leaving it too long between each bout of watering) whereas brown leaves that fall off indicate that the hoya is severely drought-stressed and probably suffering with low humidity or unfavorably high temperatures as well.
It can sometimes be the case that when the potting soil dries out completely or is heated up due to indoor heating, it can bake hard and repel water off the surface, preventing it from infiltrating the soil properly and reaching the roots.
After watering, the hoyas pot should be noticeably heavier as the soil should be evenly moist, whereas if the soil is repelling water then the excess water is likely to trickle out the drainage holes in the base and the pot does not feel as heavy.
How To Revive a Hoya with Yellow Leaves
To revive a hoya with yellow leaves it is essential to identify what specific environmental stress is causing the leaves to turn yellow and then address it.
If you are watering the hoya more than once per week or that drainage is poor and the soil feels boggy then this is likely the cause of yellowing leaves:
- Hoyas should only be watered when the top 2 inches of potting soil feels dry. How long it takes for the top 2 inches to dry varies according to temperatures, sunlight, time of year, and the plant’s maturity, so monitor the soil moisture regularly. I personally find the most reliable indicator of soil moisture is to feel the soil to a finger’s depth to detect when the soil starts to feel dry. I also lift the pot periodically to assess the weight of the pot. As the soil dries it should feel progressively lighter and you can judge when it needs watering.
- Water your hoya a lot less in the Winter while it is dormant. I usually go three weeks or so between each bout of watering for my hoya plants in the Winter. The demand for moisture is much lower when the plant is dormant (due to fewer hours of light) so if you water it too often in Winter the soil stays moist for too long, causing the leaves to turn yellow.
- If the soil is compacted (perhaps due to repotting) or poor draining then repot your hoya in the Spring. Houseplants are more resilient to the stress of repotting in the Spring. Re-pot the hoya in 1 part orchid potting mix to one part potting soil. Orchid potting mix provides the aerated, porous soil structure that hoyas need, which promotes good drainage and prevents the leaves from turning yellow.
- Plant hoyas in clay or terracotta pots (rather than ceramic or plastic pots) as these materials are porous which allows the potting soil to dry out more evenly, which mitigates the risk of root rot.
If any leaves are turning yellow with brown spots then cut off the brown leaves with a sterile pair or pruners.
Wipe the blades of the pruners with a cloth soaked in disinfectant to prevent fungal pathogens from spreading and dispose of the leaves in a bin. Treat the leaves with a fungicide or use neem oil (which is safe for pets) to prevent the fungus from spreading and the hoya can make a recovery.
For all other causes of yellowing leaves:
- Locate the hoya in a room with bright, indirect light. This balance of light gives the hoya enough energy to support green healthy leaves without scorching them in too much light (which can turn them yellow or brown).
- If the soil feels baked hard and appears to be hydrophobic (repels water) then submerge the root ball in a basin of lukewarm water for 10 minutes to allow water to infiltrate the soil properly. This should rehydrate the soil so that it is evenly moist and the soil structure should improve after it has been soaked. Keep watering the hoya consistently (when the top 2 inches of the soil has dried) and mist the leaves regularly to help it revive.
- Check to see whether the roots are pot bound, in which case re-pot them hoya to a pot that is around 2 inches larger in diameter. Avoid repotting to a significantly larger pot as over-potting can cause the soil to stay damp for longer than the hoya can tolerate. With more soil, the hoya’s roots can uptake the nutrients they need. Apply a general houseplant fertilizer every 2 weeks in the Spring and Summer.
Can Yellow Hoya Leaves Turn Green Again?
If the cause of the yellowing leaves is a lack of nutrients or underwatering then it is possible for the hoya’s leaves to turn green again, once the cause of environmental stress has been addressed. However, if the cause of yellowing is due to overwatering or lack of light then it is likely the yellow leaves will fall off, rather than turn green.
If you adjust the watering schedule and ensure the hoya has good drainage then the hoya should recover and regrow new green leaves in the Spring and Summer.
If the roots have been in damp soil for too long, then it is likely the roots have rotted and the only way to save the hoya is to propagate the vines from a cutting of any remaining healthy tissue. Hoyas are actually very easy to propagate. Watch this YouTube video for how to propagate hoyas:
Hoya Losing its Leaves
Typically the reason for hoya plants losing their leaves is because of cold temperatures, not enough light draughts from air conditioning, indoor heating, or open windows, or due to low humidity.
Hoyas are tropical plants and prefer high levels of humidity. The humidity indoors can be as low as 10% and drop lower with heating or air currents which is a drastic contrast to the hoya’s hot, humid natural environment.
The leaves drop as a way to prevent any further water loss due to unfavorably dry air which saps moisture from the leaves.
If the humidity is slightly too low the hoya leaves turn brown, particularly at the leaf margins, but if the humidity is very low then, they tend to drop altogether.
Hoyas prefer consistent indoor temperatures of around 65°F to 75°F (18°C to 24°C). If the hoya is on a window sill then it may be getting too cold at night, resulting in falling leaves. Open doors in Winter can also blast the hoya with cold air and result in falling leaves.
Hoyas also need bright indirect light and low light can turn the leaves yellowish and cause them to drop as the plant is not getting enough light for photosynthesis to support the leaves.
Too much water and compacted soil can also cause leaf loss, in which case reduce the frequency of watering and repot the hoya in orchid potting mix and potting soil as mentioned in the section above.
Revive a Dying Hoya That’s Losing Leaves
To revive a hoya plant that’s losing identify the cause of leaf loss and then adjust the environment so that it is favorable to the hoya, and the leaves should regrow.
- Keep the temperature range between 65°F to 75°F (18°C to 24°C) and avoid cold draughty areas of the house near open doors. It is also important to keep the hoya away from any direct sources of heat, such as a radiator.
- Locate the hoya in bright, indirect light to give the plant enough energy to regrow its leaves. A south-facing window sill has too much direct sunlight, so find a brighter room with lots of indirect light instead.
- Mist any remaining leaves regularly or relocate the hoya to a more naturally humid room in the house such as a bathroom. You can also buy a plant humidifier to create a humid microclimate around the hoya’s leaves which emulates the humid conditions of its native environment.
- Ensure you achieve the right balance of moisture by allowing the top 2 inches of potting medium to dry between each bout of watering. This ensures that hoya is getting enough moisture to avoid drought stress yet avoids the risks associated with overwatering.
Once you have created a more favorable environment for your hoya the leaves can start to regrow in the Spring.
Hoyas are slow-growing plants but you should start to see some new growth in the Spring and Summer, in which case apply a general all-purpose fertilizer to ensure that hoya has the nutrients it requires to grow.
Hoya Leaves Turning Brown and Dying
Most often the reason for hoya leaves turning brown is because the plant is in too much direct sunlight. Hoya plants are climbers in their native environment, so they are typically sheltered from direct sunlight by a canopy of leaves.
If the hoya is in intense afternoon sun then the leaves are likely to scorch brown.
The leaves can also turn brown due to drought stress, usually from a combination of:
- Low humidity.
- Not watering often enough, or watering too lightly.
- The hoya’s pot is too near indoor heating which can dry out the soil too quickly before the roots can uptake the moisture.
Hoya plants are native to tropical climates so they can often suffer if the air is dry indoors due to air conditioning, indoor heating, or cold draughty areas of the house.
If the drought stress is extensive then the leaves may also fall off, as the hoya tries to avoid further loss of moisture.
If the leaves and stems are turning brown or black and you are watering regularly, then this is likely a fungal disease caused by overwatering, slow-draining soils, and poor drainage.
How to Revive Dying Hoya Plants with Brown Leaves
The hoya’s leaves only turn brown due to environmental stress, so to revive it you need to identify what specifically about its environment and the conditions you are providing it with, is causing the leaves to turn brown and then to alter the conditions to suit the hoya.
If the air is dry due to air conditioning or indoor heating or you live in a climate of low humidity, then mist the leaves regularly (as often as every day) to create a humid microclimate around the hoya and move the hoya to an area without significant air currents. You can also buy a humidifier if misting every day is impractical.
If the soil is dry then I would recommend submerging the root ball in water for 10 minutes or so initially so that the dry soil can properly absorb the moisture, but it is important to emphasize that hoya houseplants need a really good soak when watering, so that the soil is evenly moist.
So always water thoroughly, to the extent that excess water is trickling from the drainage holes in the base, which indicates the moisture has infiltrated the soil and therefore reaches the roots where it is required.
Move the hoya out of any direct sunlight, to a location with bright indirect light and keep it on the other side of the room from any indoor heating.
Once the hoya’s leaves have turned brown, they do not turn green again. The brown leaves may still fall off even if you have addressed the cause of the environmental stress.
However once you have created a more favorable environment then the hoya should begin to recover and new growth should emerge in the Spring and Summer, at which point you can cut back any brown leaves back to the the vine with a sharp pair of pruners.
Hoya Houseplant Not Growing
Hoya plants are notoriously slow growers when grown as houseplants and are likely to grow much slower than other foliage houseplants, so if the plant looks healthy, there is likely nothing wrong with your hoya.
Hoyas are also likely to go dormant in Winter when grown indoors and not grow at all for months.
However, if your plant is growing slowly there are a few things to check to ensure your plant is growing properly and to its full potential.
- Place the hoya in a really bright room (without direct sunlight on the leaves) to give it the energy it needs to grow.
- Check to see where the roots are pot bound, in which case repot the hoya (ideally in the Spring) to a pot that is 1 or 2 inches larger than its previous pot (to avoid problems associated with overpotting). The additional potting soil has more nutrients and more space for the roots to grow.
- Apply a fertilizer at half strength in the Spring and Summer. I personally recommend a general houseplant fertilizer applied at half strength because too much fertilizer causes more problems than insufficient fertilizer. The roots of the epiphytic hoya are more sensitive than other houseplants and can therefore burn with too much fertilizer.
- Keep the temperature range at about 65°F to 75°F (18°C to 24°C). with around 10 degrees cooler at night. Hoyas are tropical plants native to warm climates If the temperature is too low then this can slow the rate of growth substantially and even cause the leaves to turn yellow and drop off.
- Keep the humidity high by relocating the hoya to a bathroom, using a humidifier, misting the leaves, or placing the hoya’s pot in a tray of water with the pot propped up on pebbles (so that the pot is out of the water). The water then evaporates from the tray, providing a consistent source of humidity.
- A dying hoya is often a result of root rot caused by overwatering and poor drainage. Hoyas need the top 2 inches of soil to dry between each bout of watering. Consistently overwatered soil causes the hoya’s leaves to turn yellow and drop off.
- Hoyas lose their leaves if the temperature is too cold at night or if they do not have enough light. Overwatering and underwatering can also cause the leaves to drop.
- Hoya leaves can turn brown for the following reasons: Underwatering, low humidity, too much sunlight, or high temperatures. If the stem is turning brown or black this is because of fungal diseases caused by overwatering.
- Hoya leaves wrinkles if the humidity is too low. The humidity indoors is significantly lower than in their native tropical habitat. Mist the leaves to prevent them from wrinkling.
- Hoyas are very slow-growing plants and often stop growing at all in Fall and Winter in response to fewer hours of light. To promote growth locate the hoya in a bright warm room, increase the humidity apply fertilizer in Spring, and ensure the hoya’s roots are not pot-bound.
- To revive a dying hoya recreate some of the conditions of its native environment by increasing the humidity, maintaining warm temperatures, locating the hoya in bright indirect light, and only watering the top 2 inches of the soil starts to feel dry.