Hoya imbricata is yet another plant that belongs to the Hoya genus (Apocynaceae). It is an epiphyte, which means that it anchors itself onto other plants or tree trunks. However, it doesn’t steal nutrients from its host. Rather, it collects the precious liquid and nourishing particles from other sources, such as air, rain, or dead leaves that accumulate around the base. So, we can say it is living on air.
Care highlights: Hoya imbricata can be a bit of a challenging climber, though a rare one. It requires support in the form of a solid surface, warm temperatures, high humidity levels, bright indirect light, or dappled shade if you are growing it outdoors. It is not a heavy feeder. Water it when the surface becomes dry, more frequently during the growing season, less so in the winter. Don’t worry that ants will find their way into your home if you provide a more or less hermetic environment.
Here’s the opportunity to find out how you can tend to Hoya imbricata, keep it healthy and thriving. These are the fields we shall go through:
- A word or two about the Hoya genus
- Introducing Hoya imbricata
- Where can you grow Hoya imbricata?
- What type of light does it prefer?
- Temperature requirements
- Does it require higher humidity?
- How to make a good watering schedule?
- Which type of soil is most appropriate?
- Is it wise to repot it too often?
- How important is fertilizing?
- Is pruning necessary at all?
- How to propagate Hoya Imbricata?
- Common issues and how to get rid of them
- Frequently asked questions
- A Word or Two About the Hoya Genus
- Introducing Hoya imbricata
- Where Can You Grow Hoya Imbricata?
- What Type of Light Does it Prefer?
- Temperature Requirements
- Does it Require Higher Humidity?
- How to Make a Good Watering Schedule?
- Which Type of Soil Is Most Appropriate?
- Is it Wise to Repot It Too Often?
- How Important is Fertilizing?
- Is Pruning Necessary at All?
- How to Propagate Hoya Imbricata?
- Common Issues and How to Get Rid of Them
- Frequently Asked Questions
- Final Thoughts
A Word or Two About the Hoya Genus
This genus gathers more than 200 species of evergreen climbing, epiphytic and shrubby perennials collectively known as wax plants. Gardeners often keep them for their waxy, fleshy, often succulent, or xeric leaves and scented waxy or hairy star-shaped flowers in clusters with beautiful corolla centers.
Hoya plants are grown in humus-rich, well-drained soil, either as houseplants or in hanging baskets in mild climates. Most need plenty of filtered light to bloom well. Their stems require firm support and crowded stems should be cut back and thinned out after flowering or in the spring.
Hoyas should be watered moderately when in full growth, sparingly at other times. You use semi-ripe cuttings to propagate them, preferably in late summer.
In case you want to meet other members of the family, here’s the chance:
Introducing Hoya imbricata
Hoya imbricata is native to Indonesia and the Philippines. It can be found in the wild, clinging to the trunks and large branches of trees such as Mango and breadfruit for support.
This plant comes in several forms. One has a deep cleft at the leaf base, the variety called “basi-subcordata”. Other variations can occur in leaf color, markings, and flower size, which is ascribed to flower age but could also be genetic.
This particular species is mostly grown for its luxuriant foliage and symbiotic relationship with ants. One might think that ants have a detrimental effect on this plant, but that is far from the truth since both the plant and ants benefit from this relationship.
Hoya imbricata serves as a shelter and home for ants, and in turn, ants protect the plant from other insects and provide it with nutrients such as carbon dioxide which is crucial for producing sugar necessary in the process of photosynthesis.
The stems of this Hoya are climbing, rooting at the nodes, and densely appressed to the bark, and so are leaves. A leaf develops at the node and as growth continues, the next leaf base covers the edge of the last leaf, leaving an overlapping shingle effect “imbricate”, hence the name of the plant itself.
So, the leaves can be described as imbricate, very shortly petiolate, lamina circular, raised like a watch-glass, rounded and concave on the underside leaves. The lower face is purple and the tip is obtuse to rounded. Only one leaf covers a node. One of the normal pairs of leaves aborts or never forms.
Under each concave leaf surface is a fine network of roots that help to hold the plant in place and absorb nutrients. These coverings are ideal homes for ants and if you were to pull off a stem, you would see the ants pouring out like a small swarming army.
Around 5-10 cream-flowered flowers form umbel-like clusters that are held upright. Flowers have fuzzy yellowish reflexed corolla lobes and a crown at the center, as well as anther appendages that make a little tuft in the center.
Altogether, the inflorescence is many-flowered, erect, concave with peduncles that are bent, green, glabrous, and variable in length.
Where Can You Grow Hoya Imbricata?
In case you choose to cultivate Hoya imbricata in a greenhouse, try growing it on a slab of tree bark or a large section of tree trunk or limb. If grown off a substrate, the leaves will curl up and ball around the stem.
The plant can be grown outdoors in tropical and subtropical areas, but if you don’t live in such an area, consider growing it indoors. Don’t worry about ants in your house, since if you grow it in a more or less sealed environment, the likelihood of it attracting ants is almost non-existent.
Do not forget to provide good support.
What Type of Light Does it Prefer?
A sunny room is an obvious place to display houseplants, but the spot has to be chosen carefully if you want them to thrive. It prefers bright indirect or a bright dappled shade if grown outdoors.
A south-facing window is not the best option for Hoya imbricata since it can’t stand intense, direct sunlight. It may damage the foliage. In case it is your only option, protect the plant by using a cloth and creating at least fifty percent shade.
If your plant receives insufficient light, you can supplement it by using grow lights or fluorescent tubes. They should be approximately a few inches above the plant and keep them on from 7 to 14 hours per day. The exact hours will depend on the amount of actual sunlight it receives.
? Related: 8 Best Grow Lights and Buying Guide
Hoya plants originate from tropics or subtropics and this is reflected in the temperature requirements that they need to grow well.
Hoya imbricata prefers to grow in warm temperatures. In summer, the temperature should be above 25 degrees C, but in the colder months, it should not fall below 10 degrees C. Young plants and seedlings grow best at 15-21 degrees C, away from direct sunlight.
In case you need an additional source to keep the temperature higher, consider buying artificial lights. Never site your plants directly over or below any source of heat. Those include a fireplace, air-conditioning, artificial lighting. Just to clarify, the “artificial light” here doesn’t refer to grow lights, but to regular lighting in your home.
Moreover, keep the plant away from drafty windows. Also, move it away from the windowsill at night in the winter.
Does it Require Higher Humidity?
All indoor plants need a certain level of humidity to sustain them during transpiration. The warmer the air, the drier it tends to be and consequently, the plant is losing water a lot more quickly.
So, increasing humidity levels, or the amount of water vapor held in the air is vitally important. Hoya imrbicata needs quite a humid environment to thrive, above 60 %. The higher the humidity level, the faster the plant grows.
The easiest way to increase it is to group your plants and mist them once a day. In this way, evaporation is trapped under several layers of foliage, causing a moist microclimate to form around the plants. Tray pebbles, moss lining, and getting a humidifier are some other options you can try.
How to Make a Good Watering Schedule?
When it comes to watering, you should think a few steps ahead. This involves choosing a well-draining growing medium. The ideal one should retain water well and have an adequate drainage system at the same time. These two are the prerequisites regardless of the type of plants you have.
Having done that, now you can think of the watering pattern your Hoya imbricata requires. The amount of watering this species needs depends on the season and the spot where you have placed it.
Water more thoroughly and more frequently during the growing season and less frequently and sparingly in the winter months. If you position your plant closer to the window and the air is dry, the plant will require more frequent watering.
On the other hand, if you keep your plant near the east or north-facing window, it will need less water. Check if your plant needs the precious liquid every week.
Observe how the plant reacts to your watering habits and adapt them accordingly. Avoid overwatering by all means.
Which Type of Soil Is Most Appropriate?
Plants have certain requirements of the medium in which they are growing, whether it is indoors or outdoors.
They need a firm anchorage for their roots, the right pH level, as well as the readily accessible supply of water, air, and nutrients, a healthy environment free of pests and diseases. Since the content of the soil plays a crucial role in the general health of the plant, choose it wisely.
For instance, you can combine one-third of each of these ingredients: peat as a growing medium, perlite as drainage addition, and orchid potting mix. The ideal pH is neutral to mildly acidic (6.9 to 7.5).
Do remember to provide good support for your Hoya Imbricata. For example, cork bark slabs or use longer tree branches to wire the plant against it until the root system has been formed.
Related: Best Potting Soil for Indoor Plants
Is it Wise to Repot It Too Often?
Like other Hoya plants, Hoya imbricata prefers to stay a bit root bound, so refrain from repotting frequently. Repotting once in two to three years is fine.
These are the scenarios that could require repotting:
- The plant has developed root rot
- It suffers from overfertilizing or overwatering
- Your Hoya has outgrown the pot
The soil is simply too old, dense, and doesn’t drain or retain water well.
If you have just got your Hoya imbricata in a nursery pot and it is a young plant, it can stay in it without any problems.
However, if you want to get a mature plant, ask when it has last been repotted. It can happen that the plant has been standing in the same soil for two years before you got it.
To repot, remove the old soil (from the roots as well) and choose a slightly larger pot, ideally a terracotta one, add fresh soil and some fertilizer if necessary and continue to water it as per usual.
How Important is Fertilizing?
While fertilizers cannot compensate for the nutrients produced otherwise by warm temperatures, sunlight, and adequate watering, they can support and enhance the growing medium.
Fertilizing should be done once a month during the season of active growth and never during the winter. The fertilizer should be well balanced, so follow the manufacturer’s directions, but weakened. Do not overfertilize.
Organic fertilizers are much preferred over synthetic ones, being made from a plant or animal-based and absorbed slowly by the plant. Inorganic fertilizers are mineral-based and tend to be fast-acting and the concentration used should be reduced by half of the recommended strength.
Make sure the fertilizer you are using contains nitrogen for leaves and shoots, phosphorous for roots, and potassium for flowers. As the bud develops, increase potassium.
You can also use a liquid fertilizer. However, keep in mind that it is absorbed more quickly than the solid one, which is added to the soil when the plant is potted or as a top dressing on the surface of the plant.
Some people like to use pins and spikes or even pens and push the fertilizer into the soil. But mind you, do not push too close to the roots of your Hoya Imbricata.
Is Pruning Necessary at All?
Not only does pruning control vigor, prevent rot and fungal attack, but it is also a method for promoting flowering. Mind you, wear protective gloves when pruning.
The benefit of pruning is the greatest in spring when new growth will emerge more quickly. Since it emerges from the old spurs, refrain from removing those stems that have peduncles so as not to deprive yourself of the so desperately wanted blooms.
That said, the position of the cut is crucial. Too close to the bud and it dies, too far away and the dying stub of the stem is a target for disease.
TIP: If the buds are alternate, the cut should slant upward to just above an outward-facing bud, without touching it. In the case of opposite buds, make a clean cut straight across the stem above the buds.
How to Propagate Hoya Imbricata?
The easiest way to propagate Hoya imbricata is from stem cuttings. Spring and summer are the best times to take cuttings since the plant is actively growing and light levels are high.
However, avoid taking cuttings when the plant is flowering. That’s because flowering shoots will not flower successfully, wasting your time, soil, the cutting, and the hope of seeing new growth.
Follow these 6 steps for successful propagation:
- Firstly, sterilize your shears or a knife with alcohol.
- Next, remove the stem of the Hoya Imbricata parent plant that has up to three nodes and is up to 6 inches long. In case your cutting has some leaves, remove most of them, especially at the bottom of the stem. There should be no buds or flowers on the cutting.
- Thirdly, since the cutting no longer receives the moisture from the parent plant, it needs additional moisture. Place the cutting in a jar of water, held vertically with the help of foil. You can also use sphagnum moss for the same purpose.
- The optional step is to use rooting hormones in liquid or powder form to foster the process of root production.
- When the roots appear, the cutting can be transferred to a soil mix and planted.
- For additional moisture, you can create a temporary terrarium from a plastic bag.
Related: Hoya Plant Propagation Guide
Common Issues and How to Get Rid of Them
Even the best cared-for plant can fall victim to random pests and diseases. The best advice to give is to diagnose the problem and nip it in the bud. To prevent any issues, take good care of the plant and maintain good hygiene of your growing environment.
The most prevalent issues with Hoya imbricata are mealybugs, found on leaf undersides and around the roots, producing white wax, and aphids, sap-sucking insects feeding on soft new growth. To safeguard against them, do not overwater or overfertilize, and when you do, use organic fertilizers.
If they appear, remove the leaves that have been largely infected. To treat other leaves, take a cotton swab and dab it in alcohol, then clean the foliage. There’s an alternative- a soap-based spray such as Castille soap.
The remedy for both mealybugs and aphids is to spray them with insecticidal soap or use a systemic insecticide pin. Once both of these insects are done feeding on your plant, they will leave a honey-like sap that can attract ants and other insects.
In case your Hoya imbricata attracts ants inside your home, you can use a toothbrush to remove them from the leaves.
Frequently Asked Questions
Why does my Hoya Imbricata look limp?
Inadequate watering is the cause. It’s either receiving too little or too much of it. You can start by rearranging the schedule, but if that doesn’t help, then you should inspect the roots.
What effect do coffee grounds have on Hoya Imbricata?
This ingredient serves as an excellent stabilizer of the pH level. If the soil is too basic or too acidic, it will adjust the level to neutral. Such soil will provide the best nourishing particles for this plant.
Why do Hoya Imbricata leaves fall off?
The most common reason for this is too low temperature. So, to stop this and prevent from repeating, move it to some warmer and more humid place.
What causes the extended nodes on Hoya Imbricata?
That’s because your plant is not receiving enough light. When any plant stretches like that, it searches for the light source. Move it to some brighter location.
Hoya imbricata has a fearsome reputation as “The ant-plant“ and many are deterred by the thought of it. Besides, many would agree that cultivating this variety of Hoya is a bit of a daunting task, but if you are a risk-taker and you like challenges, or you just happen to be a Hoya plant collector, it is worth giving it a try. Only then will you be able to tell if the plant is living up to its reputation or not.
What’s your two cents on ants and Hoya Imbricata? I’m curious to hear, so hit the comments section below and share your impressions with me!