Last updated on August 25th, 2023 at 12:08 pm
The hoya lacunosa is a plant with an interesting history. It was originally discovered in 1821 by Carl Ludwig Weinmann, but was not given a name until 1854 when it was named hoya lacunosa. The plant is one of many plants that we see every day and never give much thought to because they look so similar to other plants.
The hoya lacunosa is a hoya that has many different names, but it doesn’t matter what you call it. It is one of the most popular hoyas because of its striking flowers and their long periods of blooming. This hoya can be found in places like India, Sri Lanka, Madagascar, Thailand, and Malaysia.
Origin and description
Hoya lacunosa is a vine-like plant with glossy leaves. Hoya plants are native to tropical regions of Southeast Asia, Australia, and Africa. They grow in thick or shady forests near streams on limestone slopes at altitudes between 400m and 1200m above sea level. There are more than 200 species known within the Hoya genus.
Hoya lacunosa has shiny green leaves that reach up to six inches in length and three or four centimeters in width. The species is known for its waxy translucent surface, which gives it a peculiar appearance resembling small transparent ponds on the leaf tissue (hence the name ‘lacunosa’). This feature allows light to pass through the leaf tissue and provides a striking contrast between the green veins of the leaves. The flowers are white, about an inch in diameter, emerging from a woody flower stem that can reach up to two meters in height.
The species was first described by French botanist René Louiche Desfontaines (1750-1833) in 1798. Desfontaines was a French botanist who studied medicine and pharmacology but became interested in botany after the death of his father left him with enough wealth to devote himself to natural history pursuits.
Hoya lacunosa is found throughout Southeast Asia including Vietnam, Thailand, Java, Sumatra, Malaysia, and the Philippines. It is found growing on rocks or trees in forests at elevations between 700m to 1800m above sea level.
Hoya lacunosa propagation
Propagation of Hoya Lacunosa is by cuttings or seeds. I prefer propagation from cuttings as the plants tend to have a more uniform look and they are easier for me to control. Cuttings can be taken in late spring, summer, or early fall after you see some new growth on your plant.
Remove a piece of the plant that has a leaf attached and is about three to four inches long with a clean sharp knife. Remove all bottom leaves except for two as these will help absorb water while rooting in the soil. Dip the cutting into hormone powder or liquid, I use Superthrive, then place it in moist vermiculite.
Keep your cuttings in a warm area that receives bright light but no direct sun. Rooting should take place in about six to eight weeks and can be spread out over many months if you are not ready for more plants yet. Hoya Lacunosa will readily root at room temperature, so there is no need to keep the cuttings hot or cold to induce rooting.
After the cuttings have rooted well, pot them up in a peat-based soil mix and keep them moist but not wet until they are ready to be put into a larger container after you see new growth at the end of each branch.
Hoya lacunosa care
Hoya Lacunosa is an easy plant to care for. It needs bright light but no direct sun and tolerates lower levels of humidity well, making it a good houseplant in most areas. Water weekly with room temperature water until the soil is completely saturated, then allow drying out between watering spells.
Light requirements
Hoya Lacunosa is a shade plant and will do best when given bright light but no direct sun. They are good plants for the office or north windows where there isn’t usually enough light for other types of houseplants.
Indirect sunlight, filtered through sheer curtains works well also if you don’t have many windows that get full bright sun.
If you want to try your plant outside for the summer, make sure it is in a shady spot with protection from wind and move back inside if the leaves start turning yellow or drop excessively.
Soil/potting mix
Hoya lacunosa is a climbing vine, so as such, it will do well in some type of hanging basket or window box. If you don’t have those options available to you, any regular potting mix for houseplants should work just fine, and be sure to use a container with drain holes on the bottom.
In general, if you have well-draining soil, your plant should be kept evenly moist but never too wet or soggy because that will encourage root rot.
Watering
This plant can be a little touchy when it comes to watering. Overwatering can cause root rot and is the main reason why they are only recommended as houseplants, not good outside plants in most areas.
As mentioned above, hoya lacunosa doesn’t like to be too wet so try not to get their leaves or flowers excessively wet. A good way to tell if the plant needs water is by looking at its leaves and stems
If they start curling under or look floppy it’s time for some water because that means your plant isn’t getting enough.
On the other hand, if you’ve been underwatering and the stems start to shrivel up, it’s probably getting too much water so just give your plant a few days without any and that should help it recover nicely.
Be sure to check the potting mix every week or two for signs of compaction which can prevent water from draining through the pot properly.
If your plant is in a big container that doesn’t sit in water, you can let it dry out between watering but make sure to check more frequently for signs of under-wetting which are harder to tell on these types of plants.
If you are unsure about watering your plant, err on the side of dryness until you get a feel for how fast it drinks up moisture and then adjust accordingly.
Fertilizer
Hoya lacunosa is a heavy feeder and will appreciate occasional fertilization. Any balanced orchid or bromeliad fertilizer applied once a month should be sufficient but since it’s not a good outdoor plant, you probably shouldn’t leave your houseplants outside for the summer when they are most likely to need extra food anyway.
If you are fertilizing during winter or spring when your plant is actively growing, try to stay away from a fertilizer with a high nitrogen content because that will promote lots of green growth and not enough flowers.
As long as the leaves look healthy and any flower buds haven’t fallen off, it’s probably fine but if in doubt about what type of fertilizer to use, ask your local garden center or look up the specific fertilizer you’re using for more information.
Temperature
Hoya lacunosa is a little pickier about temperature than most houseplants. They do best in cool to average room temperatures which means somewhere between 60 and 80 degrees Fahrenheit, so they are not ideal for sunny, warm rooms or conservatories where the heat might get too high for them.
If you want to try your plant outside for the summer, make sure it is in a shady spot with protection from wind and move back inside if the leaves start turning yellow or drop excessively.
Hoya lacunosa doesn’t like cold drafts either, so be careful of any fans you might have on near your plant because that too can cause damage to its leaves and flowers.
If your plant is indoors only, you have a bit more leeway with the temperature but avoid exposing it to temperatures under 50 degrees Fahrenheit for long periods of time.
A little variance in temperature won’t hurt your plant too much, as long as it isn’t extreme either way and if all else fails, try moving your plant around until you find that perfect spot that’s just right for it.
Humidity
Hoya lacunosa isn’t too picky about humidity levels but it does prefer average to high humidity so you should aim for somewhere between 40 and 60%.
If your home has a particularly dry climate or central heating, consider making a little tray of water with pebbles in the bottom under your pot every few weeks which will add a little extra humidity to the air around your plant.
If you have a humidifier, be sure it isn’t too close or directed at your houseplant because that can cause rot and mold which will lead to brown leaves or flowers.
As long as the leaves look healthy and any flower buds haven’t fallen off it’s probably fine but if in doubt about what type of humidity to use, ask your local garden center or look up the specific humidity you’re using for more information.
Pruning
Hoya lacunosa doesn’t really need to be pruned on a regular basis but you can trim off any dead leaves and flowers as they start to wilt.
If your plant is getting too tall, it’s fine to cut some of the main stems back during repotting or whenever you’re changing its pot (just make sure to cut back to a leaf node).
If you want, you can also trim off some of the thicker branches on your plant when it’s mature and in need of repotting (just make sure not to go overboard or prune too many stems at once because that might damage the plant).
You shouldn’t have to do this very often because Hoya lacunosa doesn’t grow very quickly but if you do notice damaged or dead areas on your plant, it’s better to prune them off as soon as possible.
When to repot
Hoya lacunosa is one of the few hoyas that isn’t very fussy about when to repot it, but you should do so before your plant becomes pot-bound because then its roots will start to wrap around the inside of the container and smother each other.
You can tell if this has happened because there won’t be enough soil in the pot to surround all of its roots, which will lead to leaves that are yellow or browning around their edges and dropping off.
Repotting can involve just adding more peat moss or other organic matter on top of the old soil before putting your plant back into a new container but you might also need to gently cut off some of the roots if they’ve grown into a tight ball.
If you’re repotting, don’t forget to also cut back on any long or overgrown branches before putting your plant back in its pot so that it has enough space for new growth and isn’t lopsided.
Dormancy
Hoya lacunosa has a winter dormancy where it drops its leaves and flowers for a few months in the colder weather, but don’t worry if your plant isn’t looking so great when this happens, because that’s part of what you want to see.
If things start to look bad before your plant naturally sheds some dead or dying parts, that’s a sign that something might be wrong and you should check to see if it needs more light, water, or nutrients.
Once the leaves have fallen off, your plant is safe from any danger so feel free to give it brighter lighting during this time but don’t repot or fertilize until after dormancy has ended, otherwise, new growth might be stunted.
Hoya lacunosa flower & fragrance
Hoya lacunosa grows small bell-shaped white flowers with purple centers on its thick vines, but you might not see them unless your plant is around six months old or mature enough.
You should care for this plant the same way all year round except when it’s in dormancy during winter because that’s when it needs less light and water.
When your plant is flowering, it will need more light and fertilizer than usual so you can change the lighting to suit these needs or feed with a balanced liquid fertilizer every two weeks during warmer months (don’t feed in winter).
Hoya lacunosa flowers are small but they have an intense fragrance that might be unpleasant for some people so you might want to keep this plant in another room or away from any passing guests.
Growth rate
Hoya lacunosa is a slow grower so it will take some time to reach maturity and start flowering, but you don’t have to worry about pruning unless your plant’s leaves or flowers are damaged.
After six months of growth in good conditions, this hoya should be ready for the next step towards having blooms, but if you want to speed up the process, you can always repot, fertilize, or trim your plant’s long vines.
Toxicity
Hoya lacunosa might look a little too much like a succulent to be safe around pets and children, but it’s actually perfectly okay as long as you take care not to ingest any part of your plant.
Since the toxicity is only mild in this case, simply washing your hands after handling or pruning should remove anything that could be harmful.
If you have young children or pets, make sure to keep them away from the plant and never let them eat any part of it otherwise, they might be sick for a few days until their system clears out the toxins.
USDA Hardiness Zones
Hoya lacunosa is hardy in USDA zones 11 to 12, so it can survive outside during warm weather but you should still bring this plant inside before the temperature drops below freezing.
The hoya might not be able to handle cold winter nights without protection because its leaves will probably turn black and wither away if they get too much frost or snow.
If you don’t want your plant to die, make sure to move it somewhere with warmer temperatures during the colder months, even if this means bringing it inside where there’s more light and warmth.
Pests and diseases
Hoya lacunosa is healthy and hardy but it can still get common pests like mealybugs, whiteflies, or aphids if they land on your plant when you water.
You should look out for bugs with cotton-like substances around their bodies because these indicate that there’s a colony in the soil which could be harmful to your plant.
Since this hoya is a slow grower, it’s more likely to be susceptible to pests and diseases than other plants so you should keep an eye out for anything unusual like withering leaves or drooping vines if your plant seems sickly.
You can buy pesticides from any store that sells gardening supplies but make sure the product is safe for use on a hoya lacunosa or any other sensitive plant before trying it out.
FAQs
What’s the best way to propagate this plant if it starts growing too tall or wide for its space?
You can use cuttings from long vines with roots on them and add these small plants into new pots with fresh soil.
How often should I water my hoya lacunosa?
You can tell when your plant needs more water because the leaves will look droopy and thirsty, but you should also feel for wetness around the base of each vine to make sure they’re not too dry or sitting in puddles of standing water.
How much light should I give my hoya lacunosa?
You should keep it in a spot with bright, indirect sunlight and make sure not to put your plant too close to the window because this could lead to leaf burn.
When should I repot my hoya lacunosa?
You should repot your plant once every two years in the springtime to make sure it has enough room for roots to develop and stay healthy.
What are some common pests this plant might get if I don’t keep an eye on it?
You should watch out for mealybugs, whiteflies, and aphids because they can all cause damage to the leaves or roots of your hoya lacunosa.
I want to make sure my plant doesn’t have any bugs but I’m not sure how to check without harming it. What should I do?
You can use a cotton swab to dab at the leaves or stems and then bring that into your home, if you see anything with a white, cotton-like substance around its body, this means there’s a colony in the soil which could be harmful to your plant.
Where is my hoya lacunosa most likely to survive outside during warm weather?
Hoya lacunosa is usually hardy in USDA zones 11 or 12 so it can survive outdoors but you should still bring your plant inside before the temperature drops below freezing.
What’s one way I can protect my hoya lacunosa from cold winter nights without protection?
You can keep your hoya in a spot with warmer temperatures even if this means bringing it inside where there’s more light and warmth.
Can I plant my hoya lacunosa outside?
No, you shouldn’t because this species is usually hardy to USDA zones 11 or 12 so it won’t survive winter nights without protection.
Conclusion
There are several species that would be a great choice for your plant. Hoya lacunosa is another one of them and we recommend you check out our article on it to learn more about this amazing plant!
