The Hoya Imbricata is a rare species from the waxflower (Hoya) genus. They are known for their unique green bowl-shaped leaves. When mature, they also produce clusters of yellow, star-shaped flowers.
This plant can be fussier than most other Hoyas, and are best grown in a warm climate. Here’s a quick care summary:
- Plenty of bright, indirect light brings out the best growth. Choose an East or West-facing windowsill;
- Being an epiphyte, your plant prefers a light and airy potting mix that is well-draining. Equal parts peat moss, perlite, orchid potting mix, and added horticultural charcoal is ideal;
- Warm, stable temperatures and high humidity (>60%) is important;
- Mount your plant on a wooden plank, or allow it to trail down from a hanging basket;
- Mealybugs and overwatering are some of the issues you may face. Water only when the topsoil is dry, and apply neem oil to ward away pests.
Let’s dive into the details!
What is the Hoya Imbricata?
The Hoya Imbricata is a tropical houseplant from the Philippines and Indonesia with a unique growth pattern.
It starts with pairs of leaves, but one of the two aborts (dies off), and the remaining leaf oppresses itself (hugs tightly) against the host tree’s trunk. These cup-shaped leaves tend to overlap, forming a line of shingles. In fact, “Imbricata” means “overlapping.”
What’s under these cup-shaped leaves is even more fascinating! The stems and rootlets of this plant are covered by cupped leaves, providing shelter for ant colonies, earning it its nickname, Ant Plant.
However, if grown indoors, don’t worry about ant colonies – there won’t be any. 🙂
Caring for your Hoya Imbricata
The Hoya Imbricata does best in ample amounts of bright, indirect light. Choose an East or West-facing windowsill when keeping your Hoya indoors. North-facing windowsills offer the lowest light levels of all window orientations, so they must be supplemented by a grow light.
On the other hand, if you place your Hoya Imbricata in a South-facing windowsill, this may be too harsh for your plant. Long periods in the direct afternoon sun will damage its foliage and cause sun scorch, turning its leaves red. You may need to use a shade cloth or translucent curtain to reduce the light intensity.
When watering your Hoya Imbricata,
- Use the soak and dry method. Always check the top 2 inches of soil with your fingers. If it feels damp or, soil particles stick to your finger, do not water. If the soil is dry, however, you can water your plant.
- Water in the mornings, when the weather is cooler. Do not water in the midday sun, as this may cause sun scorch!
- Water your plant deeply until water escapes from the drainage hole.
- Check your plant’s soil for moisture every few days.
- Using this method, you’ll find that watering is most frequent in the spring and summer months, when your plant needs the most water, and when evaporation rates are the highest. The converse is true for the colder months when watering frequency drops significantly.
- Observe your plant: the Hoya Imbricata has thick, fleshy leaves that store water. If the leaves start to wrinkle slightly, this means that water stores are depleting. Your plant needs a drink!
Being native to subtropical Asia, your Hoya Imbricata loves warm, humid climates. Humidity should be at least 60% for a thriving Hoya Imbricata. To achieve these levels, you may need to invest in a humidifier.
Alternatively, use a pebble tray to boost humidity levels.
Aim to keep your plant above 50 degrees F (10 degrees C) at all times. Average room temperatures are perfect for your warm weather-loving plant!
As with many tropical plants, it’s essential to keep this plant away from drafty windows and doors. They don’t appreciate fluctuations in temperature or cold chills.
Like many in the Hoya genus, the Hoya Imbricata produces clusters of star-shaped flowers. The Hoya Imbricata boasts yellow-colored flowers that are fuzzy. They form umbels of 8-15 flowers each when mature.
The Hoya Imbricata has oddly-shaped leaves also feature specks of silvery-grey variegation. These large, cup-like leaves span almost a foot (30 cm) long! While these leaves shelter ants; ants protect the Hoya Imbricata from other insects and supply it with carbon dioxide essential for photosynthesis. In this way, they have a mutually beneficial relationship with ants.
At maturity, the Hoya Imbricata can grow up to 8-10 feet (2.4 – 3.0meters) tall.
Interestingly, this epiphyte has long adventitious roots growing along some stems. This plant forms long tendrils to look for other surfaces to hug and grow. If they find another location with the right amount of sunlight and moisture, they will start developing leaves that press themselves against the surface.
In this way, the Hoya Imbricata naturally seeks to expand and “colonize” other nearby locations.
When keeping a Hoya Imbricata, you can choose to let it cascade down from a high-hanging basket, or to mount it on a wooden plank. You’ll need to use sphagnum to wrap the roots around the mount. Here’s how.
Mounting a Hoya Imbricata
We figured it’s easier to refer you to this video to show you how to mount a Hoya Imbricata on wood!
Soil or Growing Medium
If you’re growing a Hoya Imbricata in a pot, selecting the right potting mix is important. Here are a couple of things to keep in mind:
- Being an epiphyte, your plant can grow in small bits of organic debris (like leaf litter or compost), or moss.
- Your plant has aerial roots, which means roots grow above-ground, allowing for maximum breathability.
- The Hoya Imbricata has succulent-like leaves that allow it to store water. This will enable it to withstand dry spells. It is also susceptible to overwatering.
Taken altogether, the best potting mix for your plant is airy, well-draining, and provides some organic nutrients.
The best soil mix for your plant is a mixture of:
- 1 part sphagnum peat moss
- 1 part perlite
- 1 part orchid potting mix
- a handful of horticultural charcoal
Such a mix best mimics your plant’s native environment and gives it nutrients to support healthy growth.
Hoya Imbricata is a light feeder, but enjoy a good dose of high-quality liquid fertilizer for best growth.
- We like using a liquid fertilizer blend that is high in nitrogen, which stimulates foliage growth.
- In the flowering season, we then switch over to a high-phosphorous fertilizer, which encourages blooms.
- Apply liquid fertilizer fortnightly during the spring and summer months, at half-strength.
- Hold off fertilizing during the fall and winter – your plant does not need it!
We repot our Hoya Imbricata once every four years, as they like to stay a little root-bound.
You’ll know it’s time to repot your plant when you see roots poking out of the drainage hole or circling above the soil’s surface. Alternatively, squeeze your pot; it should feel like it has some give. If you feel a lot of resistance, this means roots are starting to press against the pot.
Other signs include water that drains through the pot immediately without being absorbed; or your plant appearing extremely thirsty (insatiably so!).
Water your plant thoroughly a day before repotting. This helps your plant move out of its pot more easily and reduces the risk of transport shock. When repotting,
- Place your plant on its side.
- Use your fingers to gently remove your plant from its pot, working through any bits of compacted soil and teasing out the roots without damaging them.
- Prepare FRESH potting mix (as nutrients deplete over time) and a new pot about 2 inches larger than the original; fill up to 1/4 of the container. Terracotta pots are a great option as they are porous and breathable.
- Place the rooted plant in the pot, and add potting soil to secure your plant in place.
- Pat down gently, but don’t be too hard as this will compact the soil!
- Refrain from watering for about a week, giving any damaged roots time to heal.
Your Hoya Imbricata is not considered toxic to humans or animals. However, being from the Apocynaceae (milkweed) family, it does have a milky sap that may be irritating to sensitive skin. For this reason, always use gardening gloves when pruning or propagating your Hoya Imbricata or any plant from the Hoya genus!
Hoya Imbricata is easy to propagate in the spring or summer when your plant is actively growing. Here’s how:
Propagation through stem cuttings
- Identify a healthy part of the stem about 4-6 inches long, has at least 2-3 nodes, 3 or more leaves, and does not have any buds or flowers.
- Using clean garden shears, cut off the identified stem.
- Trim off any leaves from the bottom half of the stem cutting, if any (as this will be submerged).
- Apply a rooting hormone to the stem cutting.
- Prepare a jar half-filled with room-temperature water.
- Place the cutting in the water jar.
- Use a clear plastic bag with holes in it and place it above the water jar to increase humidity levels. You can use wooden sticks to hold the plastic bag up in place. Or, place a humidifier next to the water jar, set at 80% humidity.
- Replace the water every few days. Remove the bag for an hour a day for the plant to get some fresh air.
- In about three weeks, roots should start to develop.
- When roots are about 1 inch long, replant your stem cutting in its permanent pot, pre-filled with potting mix.
- Treat as you would any other Hoya Imbricata.
Using clean garden shears, prune your Hoya Imbricata. Use gardening gloves to protect your skin from the milky sap!
- Do not deadhead flowers or cut off flower peduncles (from which your flowers emerge). This is because new flowers re-use the same old peduncles!
- Being a rapidly-growing vining plant, it can get unwieldy. Prune to give a bushy shape to your plant and keep it compact.
- Trim off any dead or damaged leaves, as well as any brown stems. This allows your plant to focus its energy on new growth.
Common Pests and Diseases
The biggest issue with Hoya Imbricata is infestations from sap-sucking mealybugs.
Mealybugs are a common sap-sucking pest that infects household plants. If you spot a mealybug,
- Thoroughly inspect all your plants, including under the leaves and at leaf axils. These bugs love to hide in hard-to-reach corners!
- Quarantine any infected plants away from all other plants to prevent cross-infection.
- Using sterilized garden shears, trim off any visibly damaged or heavily-infested parts of the stems and leaves. We use 70% isopropyl solution to sterilize our gardening tools; this is important as cross-contamination is a common cause of spread.
- Apply an Insecticidal Soap spray to the remaining stems and leaves. Reapply as necessary and as the instructions dictate until you see that the infestation has been eradicated.
- Apply a neem oil solution to all other plants as a preventative measure against infestation. Neem oil disrupts the growth of larvae and prevents mealybugs from feeding, growing and reproducing.
For information on how to identify mealybugs and a step-by-step guide on killing them off, read our guide.
Why is my Hoya Imbricata drooping?
A drooping Hoya Imbricata is most commonly due to improper watering – either too much or too little! Check the Water section for tips on watering.
Why are my Hoya Imbricata’s leaves falling off?
Leaf drop in the Hoya Imbricata is most commonly due to low temperatures. Remember, your Hoya Imbricata prefers warmer weather!
What causes the extended nodes and leggy growth in a Hoya Imbricata?
Leggy growth is due to your plant searching for sunlight, as it is not receiving enough! Relocate your plant to a sunnier spot but one that is still away from direct afternoon sunlight. Alternatively, use a grow light to supplement natural light.
Frequently Asked Questions
Are coffee grounds good for a Hoya Imbricata?
There’s been some discussion that adding coffee grounds to potting soil is beneficial for Hoyas. This claim is because some Hoyas enjoy a slightly acidic to neutral potting mix.
However, most peat-based potting mixes are already slightly acidic, so we do not see the need for this, especially when using the potting mixes that we have recommended.
Also, note that coffee grounds can attract fungi growth due to their being high in organic compounds. Altogether, we caution against adding coffee grounds to your Hoya’s potting mix.
Also, note that some species like Hoya Cumingiana and Hoya Bella prefer neutral to alkaline conditions!
Is the Hoya Imbricata rare?
Yes! They are rare. You will not find the Hoya Imbricata at a local nursery or gardening center. Your best bet is looking online; we like checking out Etsy for reputable private sellers.
What’s the difference between Hoya Imbricata and Dischidia Imbricata?
The Hoya and the Dischidia genera (plural for genus) are closely related, and both are from the milkweed family (Apocynaceae). They are also both called “ant plants” thanks to the ant colonies they shelter in their leaves!
However, there are a few differences between the Hoya Imbricata and the Dischidia Imbricata:
- Dischidia Imbricata doesn’t have silver variegation on its leaves, while the Hoya Imbricata does.
- The Dischidia Imbricata produces small pinkish-red, bell-shaped flowers; while the Hoya flowers are yellow and star-shaped, appearing in clusters;
- The leaves of the Dischidia Imbricata are smaller, and kidney-shaped, while the Hoya Imbricata leaves are much larger, up to almost a foot long (30cm).
Similar Plants and Varieties
Hoya Imbricata Red Corona
This cultivar has red coronas in its flowers, instead of yellow.
Hoya Imbricata Green
The Hoya Imbricata Green has uniformly green leaves without silver variegation.
Hoya Imbricata Var Basi-subcordata
The Hoya Imbricata Var Basi-subcordata has more circular-shaped leaves and a purple underside.
Other Hoyas we Love
Hoya is a popular genus of over 500 species that are native to tropical or subtropical parts of Asia. Hailing from the milkweed family, these species are non-toxic. They are prized for their often succulent-like leaves and (sometimes scented) star-shaped flowers that emerge in clusters (umbels).
- Hoya Bella – if you are new to Hoyas, this is a good beginner-level plant!
- Hoya Pubicalyx
- Hoya Kerrii, the Sweetheart Hoya
- Hoya Elliptica
- Hoya Clemensiorum
- Hoya Carnosa Compacta, the Hindu Rope Plant
- Hoya Nummularioides – another great beginner-level plant with strong honey fragrance
Deborah is a plant enthusiast and founder of Gardening Collective.