Today's Gardener (todaysgardener.com) participates in the Amazon Services LLC Associates Program.
Hoya lacunosa is one of the species that belongs to a relatively large genus of plants, Hoya (Apocynaceae: Asclepiadoideae), differently called wax plants. This particular Hoya is an old favorite in the Hoya world. It is well adapted to various environmental conditions and extremely compact, so it fits even the smallest home.
The proper care of Hoya lacunosa includes planting it in well-draining, aerated soil in a pot that has drainage holes and letting the plant soak up lots of bright indirect sunlight, preferably the morning sun. Irrigation should be done thoroughly, but always let the soil to dry out before you re-water it. The easiest way to propagate it is from cuttings. It can barely cope in a dry and shady environment, so grow it under artificial lights with lots of humidity in that case. Be ever watchful of insects and other problems to ensure a healthy and happy life for your plant.
Continue reading to learn all pieces of information that you need to help you take tender loving care of Hoya lacunosa.
Here’s what we shall discuss:
- Introducing Hoya lacunosa
- Where can you grow it?
- What are the light requirements for this plant?
- Does it prefer a high temperature?
- Ideal humidity level for Hoya
- What type of soil does it need?
- Does it require daily watering?
- More on potting and repotting
- How to fertilize it properly?
- Is pruning overly complicated?
- Propagation essentials
- Diseases and insects
- Frequently asked questions
Let’s get down to business, shall we?
Introducing Hoya lacunosa
This compact species is an epiphytic perennial climbing vine. It used to be named Otostemma lacunosum in the old botanical literature and C. L. Blume first described it as a hoya in 1826.
It is distributed in areas such as Indonesia (Borneo, Sumatra, Java), India, China, Malaysia, Singapore, and Thailand.
The foliage of Hoya lacunosa is small, often deep green, lamina ovate or lanceolate. The sections between the veins are slightly sunken, which alters the ordinary flat surface.
Moreover, the leaf blades are decently shiny, growing on long, thin, and glabrous stems that are rooting at the nodes. This feature makes them ideal hanging basket plants. The smooth, thick petioles are 4 mm long.
The most outstanding feature of Hoya lacunosa is its inflorescence. It blooms with flat, button-shaped, whitish, pubescent clusters of around twenty convex and pendant flowers in each umbel.
Each flower resembles a tiny ball of white fuzz with a yellow star at the center that looks like a crystal. If a sunny-side-up was a plant, this is how it would look like pretty much, having suffered a mutation.
However, immature flowers need time to develop white fuzzy balls and when the flowers initially open, the petals won’t fold back at first. Observe the clusters for a few days to see how the flowers take on normal appearance as the cluster matures.
Hoya lacunosa flowers readily and often, namely in spring, summer and fall, so it will give you many exotic blooms. Do not remove the peduncles once it stops blooming because it re-flowers the old spurs. The flowers stay open for five days and produce little or no nectar.
Not only are the flowers extraordinary, but the scent that Hoya lacunosa releases is lovely, too. It is a superb, sweet, and rich cinnamon scent that is the most noticeable during the evening.
Varieties of Hoya lacunosa
There are several cultivars of Hoya lacunosa, all resembling the parent plant. These are:
- Hoya lacunosa ‘Langkawi Island’
- Hoya lacunosa ‘Ruby Sue’
- Hoya lacunosa ‘Tove’
- Hoya lacunosa ‘Snow Caps’ or H.l. Albo
Aside from these, some of the most commonly kept members of the lovely Hoya family are:
Where Can You Grow It?
This cinnamon-scented plant performs well in USDA zones 10a to 11b and can grow up to 7 meters in height.
It looks best when grown in a hanging pot or basket, for instance in a hanging garden, embellishing your patio, terrace, balcony, entry, or porch. Besides, it looks equally dazzling indoors, in the living room or kitchen.
Make sure to find a bright, sunny spot where it will be exposed to the eyes of admirers who will be showering it with compliments.
You will also need to provide a supporting structure for the vine to climb up or choose a basket and let the stems fall. It looks great either way.
If you are short of ideas, try finding inspiration on the Internet and use your imagination to design pots and construct hangers.
Hoya lacunosa is an attractive and low-maintenance plant that blooms often. For that reason, it makes a perfect indoor plant and it should find a way into everyone’s collection.
What follows is a detailed guide on how to care for this exotic plant.
What Are the Light Requirements for This Plant?
Like most Hoya plants, this dense vining perennial variety needs bright indirect light as one of the prerequisites for the successful process of photosynthesis.
A plant performs best in the same cycle of dark and light periods that closely resemble its original habitats. This is otherwise called photoperiodism. As far as Hoya lacunosa is concerned, it can grow regardless of the length of its day, as long as there is a definite period of light and darkness.
Outdoors and in greenhouses, Hoya lacunosa usually receives enough sunlight and darkness, but growing it indoors requires careful planning. Make sure to determine the right amount of light and find the best spot which can change depending on different angles and intensities of sunlight.
Adequate sunlight will ensure that the plant produces abundant leaves and blooms that are lush and luxuriant. Avoid strong, direct light and shadier spots that can impede the blooming process.
Artificial lighting as an option
You can also grow Hoya lacunosa under artificial lighting, on the condition that it is at a distance from the plants and preferably having a blowing fan to ensure that the air does not get dry and that the plant does not get rusty spots.
Keep it on for up to 14 hours a day if it is your only source of light, and use it as a supplementary light in case your plants receive insufficient sunlight.
Does It Prefer High Temperature?
This particular Hoya is very hardy and tolerant of conditions that are not ideal, but it can’t withstand colder temperatures and frost.
? Remember the golden rule: The ideal temperature for growing Hoya lacunosa is between 20 and 25 degrees C and should never fall between 15 degrees C. This is another prerequisite for the successful process of photosynthesis.
Moreover, protect it from draughts and, should the temperatures drop below 15 degrees in the colder months, make sure to bring the plant indoors.
Indoors, you can have the role of a windowsill gardener, a basement gardener, or a plant room gardener.
Ideal Humidity Level for Hoya
Apart from warm temperatures and sufficient sunlight, Hoya lacunosa, like most Hoya plants, also needs the proper amount of humidity.
This plant prefers moderate to slightly higher humidity levels, between 40 and 60%.
There are many means to prevent the air from becoming dry. Firstly, you can mist the plant with filtered or distilled water. Secondly, you can place pebbles on a tray filled with water and put the plant on top. Finally, you can get a humidifier. This is especially important if you keep your plant close to the heating system, but try to avoid that.
What Type of Soil Does it Need?
Since this Hoya is an epiphytic plant, it collects nutrients from the air, rain or water, sun, and the debris gathering around it. It adapts easily to versatile potting mediums that other species would find not so friendly, to say so.
Commercial, all-purpose potting mixtures are readily available and are usually suitable for most houseplants. The mix usually contains peat moss, ground bark, sterilized manure, composted leaf mold, rice hulls, and some substances for aeration such as coarse sand, perlite, vermiculite. Check the back of the bag to see if the ingredients match.
Should you want to make your own mix, you can purchase these ingredients separately or even use your garden soil as a base, sterilize it in the oven for about an hour at 180 degrees and then add the organic amendments such as those mentioned above.
In any case, remember that the soil should be well-draining, and well-aerated to prevent root rot, moisture-retentive but not water clogging.
Besides, the potting mix should be neutral to slightly acidic.
Related: Best Potting Soil for Indoor Plants
Does it Require Daily Watering?
Here we need to consider the same level of humidity that the plant gets in its original living surroundings. Since Hoya plants are tropical or semi-tropical, they can get well by neglectful watering.
The golden rule here is to water thoroughly until the water drains out the holes and allows the top surface of the soil to dry between waterings.
Ideally, you want to use natural rainwater, but this is not essential.
✔️ Useful trick: Soak the banana peel in water overnight and water the plant the following day since it is said to contain healthy nutrients.
Avoid overwatering so as not to impede the general health of the plant.
Observe how the leaves of the plant are looking to determine whether the plant needs watering and if in doubt, skip watering. It is better to underwater than to overwater.
Water sparingly and infrequently in the colder months and make sure to find ways to keep your plant hydrated when you are away.
More on Potting and Repotting
All epiphytes prefer to stay root-bound. For that reason, it is not advisable to repot frequently.
In truth, repot it only when absolutely necessary, as in the case of outgrowing the pot or trying to save the plant from root rot. However, you can prevent both issues by planting Hoya lacunosa in a larger pot and avoid overwatering.
When repotting, remove the old roots and soil, use rich, fresh soil. Water thoroughly and provide a spot with subdued light, then gradually accustom it to more light. Repotting before the active growth is recommended.
✍️ Things to remember when repotting:
- Choose a pot of appropriate size with drainage holes
- Be wary of overpotting
- Use a sterilized medium and pot
How to Fertilize It Properly?
Provided that you have satisfied the primary needs – adequate soil, sunlight, temperature, and humidity, your plant won’t need much fertilizing.
Ideally, you want to use organic rather than chemical fertilizers, such as decomposed leaves or bark mixed with rich soil. Balanced orchid fertilizer is another option, or a mixture of nitrogen, phosphorus, and potassium in a ratio of 20-20-20.
Fertilizing should be done during the growing season, once or twice, judiciously and in poor concentration rather than excessively. Do not fertilize in the winter since that is the period when the growth slows down and care should be limited only to water management.
Is Pruning Overly Complicated?
Pruning is a slippery subject as far as Hoya lacunosa is concerned.
When the plant flowers, do not prune or trim off the old spurs from which the flowers came since new blooms will appear again. Once the flowering period is over, you can go ahead and trim your Hoya, which will force new branches, filled with new bloom spurs.
You can also trim the plant using shears or a sharp knife to maintain the desired shape, preferably at a distance from the blooms, for the same reason.
?Growing from seeds
It is possible to grow Hoya lacunosa from the seeds. The fresher the seeds, the better your chances of success with propagation.
Those seeds will germinate easily on a damp medium, such as a commercial seed sowing mix, a bed of fine peat moss, clipped sphagnum, or fine potting soil. Keep the seedlings moist, warm, and in a good light.
Then when it is time, pot the seedlings in the way described above. They won’t need any fertilizing for around a year, but if you have used other soilless media (sponge rock, vermiculite), commence moderate fertilizing once two sets of regular leaves appear.
⚠️Warning! One potential drawback of this method is that fungus disease can attack the seedlings at the soil line, causing them to die. To prevent that, spray the surface of your seedbed beforehand with a good fungicide like Benlate (Benomyl) prepared according to the directions. Snails and slugs can also attack seedlings.
?Growing from stem cuttings
This method is more widespread owing to the fact that it increases the chances of success. There are two options available, rooting in water and rooting in a solid medium.
Rooting in water
- Take short cuttings of 6″ or so in length.
- Remove the leaves from one or two nodes, since roots will emerge in nodal areas most readily due to the presence of growth hormones.
- Fill a wide jar with water, cover it with foil and poke a few holes.
- Insert the cuttings through those holes and into the water below.
- Keep the jar in a well-lit, warm and humid environment.
- You can add a dust of rooting hormone or vitamin B-1 solution to the cut end to enhance rooting.
- Do not chill the water or the plant and 72 degrees F should be ideal.
Rooting in a solid medium
- Sterilize the medium (sponge rock, fine bark chips, or loose potting soil) and the pot.
- Take short cuttings.
- Apply a rooting hormone powder and tap off the excess or add vitamin B-1 to the ends. This step is not essential.
- Lay the cuttings on the soil horizontally with the nodes covered.
- Keep the medium moist by misting, but do not saturate it.
- Firm up the potting media around the cutting.
You can experiment with different methods and see which one you like best. Remember which end is up and which one down, since the growing end does not like to be buried.
Diseases and Insects
Generally speaking, Hoyas are not susceptible to diseases. However, if not properly taken care of, it can suffer from some problems.
One of them is the fungus Phomopsis. It attacks Hoyas as do some other sooty black fungus species in high humidity conditions for extended periods. As mentioned earlier, seedlings are also subject to damp-off organisms.
Keeping your culture clean and sterile will minimize the risk of these occurrences, but if you suspect that your plants are virus-infected (fading of green along the veins or a yellowish mottling, also caused due to zinc and iron deficiency), it is best to isolate them, in some case even get rid of them.
As for insects, the most common are mealybugs and Aphids which prefer new growth and tender foliage, such as the green peach aphid, oat bird cherry aphid, and the yellow oleander aphid.
Be vigilant of other pests, too, like rodents, snails, slugs, grasshoppers, red spiders. These occur frequently outdoors or in glasshouses. Increase humidity, spray all leaves with a miticide. Do the treatment outdoors, since most sprays are poisonous.
Be sure to check the plants for pests if you are moving them indoors during the colder months.
Frequently Asked Questions
1. Is Hoya lacunosa a succulent plant?
Although this wax plant requires a similar care pattern as many succulents, it is essentially an epiphyte. Other varieties of Hoya have more succulent leaves than this particular one.
2. When does Hoya lacunosa bloom?
It blooms often, all year round, on the condition that it receives enough sunlight and humidity.
3. What are the signs of over-fertilization?
A build-up of white, crusty-looking powder will appear on the uppermost layer of your potting mix, the edges of the foliage will become dry, rusty, and shriveled and the main stem will often swell and split open. Unless you thoroughly rinse out the medium with clear water to wash out the excess fertilizer or transplant the plant, the root system will suffer and the plant may die.
4. What varieties of Hoya are the most immune to pests?
Mealybugs and Aphids seem to dislike Hoya micrantha. Other varieties like H. Obscura and H. plicata are rarely grounds for their growth. Proper care and a clean culture is the only prevention policy.
5. Can fertilizers cure a diseased plant?
Fertilizer is not a cure-all and won’t cure a diseased plant. Fertilizers should be applied to healthy plants in active growth unless the plant’s illness is a consequence of poor nutrition.
Hoya lacunosa makes an eye-catching floral display, especially when suspended in the air, either in hanging pots or baskets. Being cinnamon-scented, this fuzzy white variety will hold any visitor spellbound all year round.
In brief, to take proper care of this epiphyte you should plant it in rich, well-draining soil and provide a warm environment with enough bright indirect light, temperature levels between 18 and 24 degrees C, and humidity between 40 and 60%. Water it thoroughly when the soil surface becomes dry and propagate it from seeds or stem cuttings. Do not over-fertilize and overpot, be careful when to prune and inspect the plant for pests regularly. Tackle all the issues outside.
Now you are equipped with the necessary knowledge to grow a healthy and attractive Hoya.
What’s your favorite method for Hoya lacunose propagation? Hit the comments section below, I’d like to hear from you!