Native to Indonesia and Papua New Guinea, this vining Hoya is pretty rare and seldom finds its way into our urban jungles. It’s leaves are dark green, a little bit velvety and slouchy.
Its flowers are typical for a hoya but bigger (up to 3cm in diameter), white with bright purple/reddish centers.
What makes it special is that it is very low maintenance and fast growth, so it is perfect for beginners that want a vining flowering plant.
It is perfect if you need a plant that is going to fill up a space fast and will look magnificent spilling out of a hanging basket or trailing up a moss pole or trellis.
In this guide, we are going to explain all of the needs of this plant and what you should do to keep it healthy and problem-free.
From soil needs to propagation, keep on reading to find out everything you need to know about the Hoya calycina and more.
Table of Contents
Hoya Calycina Plant Care Guide
Soil
Like most Hoyas, the Hoya calycina is at high risk for root rot. Plant it in a well-aerated soil with enough perlite and orchid bark so as not to suffocate the roots.
One part orchid bark, one part perlite, and one part growers mix will be a well-draining medium for a plant like this.
You can also opt for coco coir or moss instead of bark, just keep in mind that the end result should be soil that can retain some moisture but will let water through fast enough.
If you err on the side of airier keep in mind you will have to water more often, but this is preferable over rotting roots and a plant that needs a troubleshoot repotting at a random time of the year.
Light
These robust Hoyas can take some direct sunlight, but optimally keep it in bright indirect light with a couple of hours of direct or dappled sunlight. Hoya calycinas are definitely not low light plants and will suffer in a darker environment. An east or west-facing window are both fine, but it will have the best time in a south-facing window with ample light.
Watering
Water your Hoya calycina when the top couple of inches of the soil is dry. You shouldn’t worry about underwatering, since these semi succulents leaves can keep the plant going for a while.
The major risk is overwatering so let them dry a little between waterings. You should spray the aerial roots with some water every now and then, and you should use distilled or rainwater whenever possible.
Hold on the watering as the plant blooming season is about to start, and water less during the winter months.
A good tip for Hoyas is also watering from below. If you planted it in a pot with drainage holes on the bottom, put your plant with its pot in another, bigger container full of water.
Leave the plant there for about half an hour to allow it to absorb the water. The soil will bring the water up to the roots by wicking, and the roots will be encouraged to grow downwards.
This makes for a more robust and secure plant and prevents overwatering and fungal issues at the top of the plant.
Temperature
The Hoya calycina had an intermediate general temperature tolerance in comparison to other Hoyas. What I mean by that is that the lowest continual temperature it should be exposed to is around 60F, while the highest is 95F.
This means that if you are keeping your Hoya outdoors you should be bringing it indoors once night temperatures drop below 60, and you should also keep it away from windows, doors, and drafts in the winter if you are living in a temperate climate.
Hallways, mudrooms, and window sills are consequently not suggested, especially in the colder months. Also, keep it away from heat sources like radiators and heaters, which can cause the plant to experience temperature shocks and drop leaves.
Humidity
Your Hoya calycina will need the standard 60% humidity like most tropical plants. It can do well in lower humidities, but it will not grow as fast and flower as much.
If you can’t afford a humidifier, try and help your plant out with pebble trays, but avoid misting it as misting such a plant is only asking for fungal issues.
Especially in the winter, you can try and elevate the humidity in your home with humidity trays or wet rags on radiators, leaving the door open when you shower, letting your clothes and dishes air-dry indoors, and placing random water containers on windowsills or shelves close to radiators.
Fertilizer
With a Hoya calycina, it is better to fertilize wisely than to fertilize more. When the plant is in its adolescent stage and is putting all of its energy into growing the vines and leaves, add liquid fertilizer for green houseplants twice a year.
Before a blooming season and as you can see new buds sprouting out, give it some bloom enhancing fertilizer rich in nitrogen.
That way you are feeding it exactly for the purpose it needs when it needs it. You can also opt for a pelleted slow-release, all-purpose fertilizer if you can’t be bothered with particular feeding.
Propagation
The best way to propagate a Hoya calycina is by stem cuttings in water. The process is pretty straight forward and easy but here is a step by step explanation on how to do it if you have any doubts:
- Choose the branch you want to cut. It should have at least a couple of nodes and a couple of leaves.
- Cut away the bottom leaves to expose a node or two, but keep at least 2 leaves.
- Let the cutting air dry for a couple of days until the wounds you cut heal over.
- Put the cutting in water so that you submerge the nodes and keep the leaves out of the water.
- Wait for a couple of weeks until a few inches of well-developed roots are present.
- At this stage, it is wise to start adding soil to the water gradually. Spoon by spoon add soil to the water every 2 to 3 days until the soil replaces the water completely. This is a good method to let the plant get used to a darker and less oxygenated environment slowly and gradually. It reduces the chances of the plant getting shocked and dying.
- Once the transition to the soil is complete, you can transfer your plant to a pot and treat this cutting as a young plant.
Keep a closer eye on recently propagated plants, as they are extra susceptible to pests and diseases at this young and fragile stage.
Keep the soil evenly moist but not soggy, and try to give young plants a little bit of extra humidity with a humidity dome or humidifier. Don’t forget to give them enough regular airflow too, to prevent rotting and molding.
Growth
We have already mentioned the Hoya calycina is a vigorous grower. For that very reason, we suggest you either plant it in a hanging basket or in a planter with a robust and high enough trellis.
It will need a lot of support, so go bigger than you think you should, as the speed of growth of this plant can take you by surprise.
They can grow up to 15 to 20 feet in length, so try to keep that in mind when choosing a good place for it in your home. As far as pruning is concerned prune only ofter the pruning season and cut the dead leaves and stems only.
Common problems with Hoya calycina
Your Hoya calycina will be susceptible to aphids and mealybugs just like most other Hoyas. Apart from that, their no. 1 enemy is root rot and mildew. Let’s go over these nasties and see what you can do to prevent and treat them.
Aphids
Aphids are often attracted to Hoyas and will feed on the sap of your plant until it dies. The leaves turn yellow and you can see the Aphids as tiny light green bugs clustering around new growth, flower buds, and around the nodes.
They often come in great numbers at once especially if your Hoya is outdoors. Blast them away with some water and treat the plant with some Neem oil or an insecticide and repeat if needed.
Mealybugs
Mealybugs are a common pest with indoor houseplants but they are relatively easy to deal with. They are slow-moving which is a plus for you.
If the infestation isn0t too bad you can remove them individually with a q-tip dipped in alcohol, but if they are returning and you can’t keep them off resort to giving your plant a good wash with insecticidal soap and a neem oil treatment afterward.
Repeat this as needed, as it is hard to get rid of them sometimes. Most pests are present on your plant in varying stages of growth, so even if you get rid of the adult bugs, larva and eggs can still be hiding in hidden crevices and in the soil.
Root rot
Although the first line of defense against root rot is prevention, we are going to suppose you did everything right but your Hoya calycinas roots are still in trouble.
Sometimes fungi and mildew spores come with the soil you bought, so it is not impossible to see root rot even in well-aerated soils.
Uproot your plant and wash away all of the soil. Inspect the roots and remove any affected roots that you can find. Then wash the rootball with a mixture of one-quarter water and a tablespoon of neem oil.
Repot this plant in new, sterile soil and hope for the best. Root rot can cause irreparable damage so be ready to throw your plant away when there is nothing more you can do.
Powdery mildew
Powdery mildew forms on leaves and stems and you can recognize it by its round, white, and slightly fluffy spots. It usually occurs when there is high humidity and not enough airflow through the plant.
The tissue under these spots and die, so plants can be completely destroyed if you don’t act fast enough.
The spots can be removed with a mixture of 1 tablespoon of baking soda, ½ teaspoon of liquid soap, and a gallon of water, but if you see that the tissue underneath is already damaged this part of the plant should be removed immediately.
Treat your Hoya calycina with Neem oil as it is a fantastic antifungal that should be able to prevent such issues before they happen.
Tips to keep your Hoya calycina problem-free
- Mist it’s aerial roots regularly
- Give it a fast draining and well-aerated soil
- Feed it with some bloom booster before blooming
- Give it a robust support system to accommodate ample growth
- Treat with Neem oil regularly
- Keep humidity high
Frequently asked questions about Hoya calycina
Why are there ants around my Hoya calycina and how do I get rid of them?
Ants around your plant are often a sign aphids are present as well. Ants feed on the sap that aphids secrete as they feed on the sap of your plant. If you see any, treat the aphids as we explained in this article, and sprinkle some cinnamon around your plant to deter ants.
My Hoya calycina’s leaves are yellowing and dropping, what should I do?
Most likely this is a sign of overwatering, especially if the first leaves to drop are closer to the soil. Let the soil dry out a little more in between waterings.
Why are the tips of my Hoya calycina turning brown and dry?
Brow and dry tips are often the result of watering your plant with hard tap water or mineral buildup because of too much fertilizer. Try watering your Hoya calycina with distilled or rainwater, and ease off on the fertilizer for a while.
Conclusion
Does the Hoya calycina sound like a plant you could master? I think so as this is a low maintenance plant that will reward your efforts with ample and fast growth.
If you like the look of a huge hanging or trailing plant somewhere in the home, the Hoya calycina could be the statement piece you are looking for.
Take care of it like you do for most other hoyas, give it ample light, and treat its aerial roots with a mist every now and then and this plant will thrive.
If you already have one, share a picture and your own tips and tricks for this plant in our Facebook group, we love hearing from our readers!
Daniel has been a plant enthusiast for over 20 years. He owns hundreds of houseplants and prepares for the chili growing seasons yearly with great anticipation. His favorite plants are plant species in the Araceae family, such as Monstera, Philodendron, and Anthurium. He also loves gardening and is growing hot peppers, tomatoes, and many more vegetables.