Hoya carnosa prefers warm temperatures in ranges between 60°F and 85°F (15°C to 29°C). It’s sensitive to drafts, air conditioners, or heaters.
Hoya carnosa can tolerate average indoor humidity levels, but it will thrive in higher humidity.
It's good to boost humidity in dryer homes by using a humidity tray, a humidifier, or occasionally misting the leaves. However, be cautious with misting, because too much moisture on the leaves can lead to fungal issues.
Soil and Potting
Hoya carnosa is commonly sold as a hanging plant, but they can be trained to climb up a trellis or pole.
They prefer a well-draining potting soil mix that does not retain moisture. Good options include succulent or cacti mixes or regular potting soil mixed with orchid mix and/or perlite. Pots with drainage holes is a must (for all other plants as well!).
Repot every 1-2 years when you notice it outgrowing the pot or that the roots are starting to come out of the drainage holes. Don't choose a very large pot, it will flower better when a little root-bound.
Fertilization
Use a balanced, water-soluble fertilizer diluted to half strength, and fertilize once a month. Avoid fertilizing in the fall and winter when the plant’s growth slows down. Over-fertilizing can lead to leggy growth or burned roots.
Some enthusiasts recommend switching to a fertilizer that has a little more phosphorus if it looks ready to bloom.
The International Hoya Association suggests feeding them with a fertilizer that includes nitrogen, phosphorus, and potassium.
Pruning and Maintenance
Hoya carnosa is a relatively slow grower and a low-maintenance plant. Prune occasionally to maintain its shape and encourage fuller growth. Don't remove the flower stalk after blooming, it will force the plant to produce a new one, wasting time and energy.
Gently wipe the leaves with a damp cloth every few weeks to remove dust and debris that accumulates.
Propagation
Fun Fact: In the wild, Hoya carnosa is pollinated by moths.
They can be propagated easily through stem cuttings.
To propagate, cut a healthy stem with at least one leaf and a few nodes. Place the cutting in water or potting mix, and keep it in a warm, bright location. After a few weeks, the cutting should develop roots and can be potted into its own container.
Flowering
Hoya carnosa is known for its beautiful flowers, which appear in clusters of star-shaped blooms. These flowers can be white, pink, or red, with a waxy texture that gives them their signature look. They smell very sweet and produce a sticky nectar that sometimes drips off. It helps to place a towel under the flowers to protect your furniture or floor.
While not all plants will flower regularly, they’re more likely to bloom if they’re in a location with plenty of bright light, warmth, and humidity. They can be slow to flower, and it may take 2 to 7 years for a plant to become mature enough to bloom.
Hoya flowers last for about a week. Never deadhead hoya flowers. Cutting off the spurs, where the flowers bloom from damages that part of the plant, and it will not bloom again the following year.
Pests
Hoya carnosa is "hardy", but still vulnerable to sap-sucking pests like aphids, mealybugs, and spider mites. All can be controlled with neem oil.
Fungal infections are also common. Botrytis blight can cause rot and kill your plant, it shows up as greyish patches.
Pet Safe?
Hoya carnosa is non-toxic to pets. However, chewing on the leaves could cause digestive upset, even though it’s not toxic.
Common Issues
- Yellowing leaves from overwatering, underwatering, or low light.
- Leggy growth from low light.
- No flowers due to lack of light, warmth, or humidity.
- Leaf drop, leaf blackening, and stem dieback due to overwatering or lack of warmth.
- Wilting due to overwatering or too much fertilizer.
So basically, most problems are due to overwatering, lack of light, and cold temperatures.
So, that's what I've learned so far. I hope this helps you decide if this beautiful plant is right for you. Any planty experts, please feel free share your wisdom in the comments (and let me know if I got something wrong).
Now I'm going to go admire the leaves on my lovely plant some more.
Stay green.
