How to Care for a Hoya Lacunosa

Introduction

A Hoya lacunosa is a very beautiful vine plant, which comes from the Indonesian Islands and is becoming a popular houseplant. You can get variegated and frosty leaved varieties, too, and it has amazing blooms with a rich cinnamon scent.

Its little white flowers are very dainty. It blooms throughout the year, and it will fill your home with both elegance and a wonderful smell. Although Hoya lacunosa plants come from tropical places, you can grow them around the world if you take a little care with their setup.

These plants require well-draining soil, a medium amount of indirect light, and some humidity. Beyond that, they are not very fussy plants, and will grow happily with minimal care or attention.

Indoor vs Outdoor Growing

These plants come from tropical climates, and outdoors, they usually grow on tree trunks, rather than directly in the ground. They are epiphytes, and they use other plants to stretch up to the canopy and get more light.

You can grow them outdoors if you live in a warm enough part of the world, and if you live in an unsuitable climate, consider growing them indoors in a pot or hanging basket. Whether you grow them indoors or outdoors, you will need to provide a supporting structure of some kind for them to grow up and trail over.

Best Location For Your Hoya Lacunosa

You can grow a Hoya lacunosa anywhere in the home, provided it has a support to climb up, and enough warmth and light. You don’t have to limit yourself to just one specific room. Choose somewhere with a big window to let the light in, and enjoy their beauty.

However, you don’t want to grow a Hoya lacunosa in very bright light. They are used to the dappled sun that comes from growing beneath a canopy, so it’s best to grow them a little way away from a window, or provide some thin shade from the sun.

You may also want to use a grow light. This plant will tolerate being grown in only medium light conditions, but it will flower much better if you grow it in full light. If you want lots of blossoms, you need to provide a good amount of either sun or artificial light. These will help to ensure that gorgeous cinnamon scent pervades your whole home.

If you plant to grow your Hoya lacunosa outside, make sure you provide some shade that will protect it from the full heat of the sun, especially in summer.

Soil For A Hoya Lacunosa

As with all epiphytes, Hoya lacunosa plants need very well draining soil. In their natural environment, they grow on tree bark, which obviously doesn’t suck up a lot of moisture – and that means they don’t like being flooded or staying wet. Normally, they will be taking up rainwater that runs down the trunk or is gathered in other plants such as moss.

They also need lots of air around their roots; they haven’t evolved to be smothered in heavy, compacted soil. Airy planting conditions are a must for Hoya lacunosa plants.

To grow them at home, you’ll usually want them planted in a pot, but you need to maximize the drainage and minimize the compaction of the growing medium. That means buying a special potting mix or making your own at home.

An orchid mix is often a good starting point, but you should also mix in perlite to improve the drainage. This will ensure the water doesn’t sit around the plant’s roots, and the orchid bark will provide nutrients and structure.

Hoya lacunosa plants like quite rich soil. Orchid bark and perlite should provide everything that they need.

Watering Your Hoya Lacunosa

As mentioned, Hoya lacunosa plants don’t like to be wet for long, but they don’t like to dry out too much either.

How often you need to water your plant will depend on where you are located in the world and how dry it is, but about once or twice a week is often sufficient in the summer months. Make sure you have a drip tray under the plant to catch excess water.

In winter, you will probably only want to water every two weeks. To get a better idea of whether your plant needs watering yet or not, push a finger into the soil to about an inch down. If the soil feels very dry, it’s time to water. If it is still wet from the last watering, wait a while longer.

Discard excess water from the tray below your plant, rather than allowing the pot to stand in it once the plant has had a drink. It will not like the “wet feet” this results in.

It’s a good idea to water Hoya lacunosa plants from the top, not the bottom. If you are unfamiliar with this, bottom watering is where you water the saucer below the plant and allow the water to soak up. Top watering is where you pour water on the soil from above.

Bottom watering is good for many plants because it encourages them to stretch their roots down into the soil, but remember that Hoya lacunosa plants grow on tree bark, and are consequently very shallow-rooted plants that don’t grow deeply at all. You are better off watering from the top so their roots can reach the liquid.

Humidity For Your Hoya Lacunosa

Although they don’t like wet feet, they do like high humidity levels, and if you’re going to grow one in a cold, dry environment, you are going to struggle. However, you can do it if you take steps to mimic their natural environment.

Hoya lacunosa plants thrive in a humidity of 60% or even higher, but they will grow in less humid conditions too. However, you should be aiming to get the humidity levels up to help your plant thrive. This can be done very simply with a spray bottle.

Mist your plant’s soil or its leaves early in the day, giving time for the moisture to evaporate before evening (as wet leaves overnight can make a plant more vulnerable to mold and fungus). You don’t need to do this every single day, but when the weather is hot and dry, it is important to keep your plant’s leaves damp.

If you would rather not have to mist daily, consider buying a humidifier that can be plugged in beside your plant. Turn this on whenever you want to increase the humidity levels in the room, and then just flick it off again in the evening, or even put it on a timer so that you don’t have to remember to alter it.

Alternatively, you can DIY a humidifier at home. You need a shallow tray with no holes in it and a bag of small stones. Pour a little water into the tray, making sure it doesn’t rise above the level of the stones. You can then stand your Hoya lacunosa’s pot in this tray, so that it rests on the stones.

The soil won’t get wet, and the water will slowly evaporate off the tray and boost the humidity around the plant. Remember to top the water up whenever the tray dries out.

Fertilizing Your Hoya Lacunosa

You can fertilize your Hoya lacunosa every couple of weeks during the growing season if you choose to. Doing so will help to boost its growth and may make it flower more, but it is not an absolute necessity.

Your Hoya lacunosa plant should grow fine even if you rarely fertilize it, as long as you are growing it in a reasonably rich soil medium.

Remember to dilute fertilizer so that it isn’t stronger than the plant can handle. Too much fertilizer or too strong a dose can cause a plant’s roots to burn, which will make it sick. It may also encourage the plant to grow a lot of leaves but very few flowers.

You don’t need to fertilize during the winter, as Hoya lacunosa plants grow very little during the cold months, and won’t need or appreciate the extra food. Cease fertilizing and resume when the weather starts to warm up and your plant becomes more active again.

Toxicity

Hoya plants are generally considered non-toxic and reasonably safe to grow near animals and children, but bear in mind that they are part of the milkweed family, and their sap has latex in.

This is intended as a deterrent to predators, and while it is not generally very threatening to humans, you shouldn’t let anyone or anything chew on the leaves of your Hoya lacunosa. Eating it in large quantities could cause harm, and even smaller quantities may result in stomach ache and nausea.

Animals and young children should be kept away from the plant. You may need to grow it in a room where they rarely go, or behind an obstacle that will keep them away. You might also be able to train your cat or dog not to go near the plant.

If all else fails, rubbing the leaves with something that will repel them (but not damage the plant) can be a good short-term solution. Chili may be a good option. You could also put something they dislike the smell of in or near the pot to keep them away from it.

Explain to your child that the plant is not for eating, and physically distance them from it if they are too young to understand this. While Hoya lacunosa plants may not be very toxic, it’s important to be careful. If your child or pet eats the leaves, talk to your doctor or vet promptly to get advice on what to do.

Remember, hoya lacunosa plants can be grown in hanging baskets, which may be a good way to get them out of reach of curious mouths.

Propagation

You can grow this plant from seed by collecting the seeds after the flowers have finished, but it is often easier to propagate it by taking cuttings from the main plant itself. Fortunately, this is pretty straightforward to do and if it goes wrong, you can easily try again at no cost!

Try to do this in the spring or summer, when the plant is active.

Make sure you sterilize all tools before you cut your plant, to avoid the possibility of transferring an infection or bacteria to the open cut.

You should select a nice, healthy stem for your cutting, to maximize your chances of success. Ideally, you want to find one that has three or four root nodes, and a few leaves. You should cut about six to eight inches from the growing end, and ideally only around a quarter of an inch from a root node.

Take off the leaves on the lower part of the stem, and then plant the cutting in a container with perlite and orchid bark. You can then put the container somewhere with medium indirect light, and gently water it. Keep it damp but not wet while the plant is getting itself established.

You should see roots appearing after about three weeks, and these will slowly develop. After about five more weeks, the cutting should start to develop new shoots.

You can also propagate the plant using water. Follow the above method, but instead of planting it in perlite and orchid bark, put it in a jar of clean water. You should allow the chlorine to evaporate off the water for a few hours first.

Push the cutting about four inches under the water, and remember to refresh the water every three days. This will help to prevent stagnation and rotting, but will also ensure that the plant gets plenty of oxygen. Using a glass jar will let you see when the roots have developed.

You can then transfer the plant to soil when it has strong enough roots. This should be done gently to avoid breakage.

If you have problems with this kind of propagation, you can try a little trick to help the plant adjust. Instead of lifting your cutting out of the water and transferring its roots to soil, try adding a spoonful of soil to the jar every day. This will help the roots adjust, gradually replacing the water without disturbing them.

Eventually, you should have a jar full of soil. Lift this out, and carefully pot the plant.

Repotting

If you’re someone who never gets around to repotting houseplants, don’t worry – because the Hoya lacunosa rarely needs to be repotted. Because they have shallow roots and they actually prefer being cramped to having too much space, you shouldn’t have to take them out of their pots very often.

In fact, you may find that you never really need to repot your Hoya lacunosa plant. If you do need to because it’s getting too crowded, you can simply lift the whole root ball out of its pot and transfer it to a new container. You don’t need to mess around trying to separate the roots out; they should sort themselves reasonably well.

You may want to top up the soil in your plant’s pot from time to time, even if you don’t repot it. Orchid bark will slowly break down over the years, and it’s a good idea to add a little more to the mix when you can. This will work perfectly well instead of repotting it.

F.A.Q.

Here are a few questions that you may want to ask about Hoya lacunosa plants, and some tips on how to solve problems with them.

Why Is My Hoya Lacunosa Losing Its Leaves?

If your plant is dropping a lot of leaves, it may be suffering from the cold. If you can relocate your plant to a warmer spot, do so. Hoya lacunosas do not like cold weather, so you need to grow them in containers if your environment is not warm in the winter.

Bring them indoors when it gets cold, and don’t take them back out until it’s warmer – and even then, harden them off by bringing them in at night but taking them out in the day.

If your plant is already inside, try moving it away from any cold windows or drafts, or turning up the heating slightly.

Why Does My Plant Have Burned Leaves?

If the leaves of your Hoya lacunosa look burned, with white or brown patchy spots near the part closest to the window, it’s because the plant is getting too much direct light. It can be a tricky balance, providing this plant with enough sun, but not too much sun.

While Hoya lacunosa plants will tolerate direct sun for a while, they don’t like very bright direct sun. If you can’t move the plant away from the windows or you’re growing it outdoors, try putting a shade up during the hottest parts of the year, or grow a sun-lover between the Hoya lacunosa and the sunshine.

You should remove leaves that have burned as the dry and damaged cells could be vulnerable to fungi, which will then infect the whole plant.

Why Is My Hoya Lacunosa Not Flowering?

Since these plants are often grown for their fabulous flowers, it’s really disappointing when your Hoya lacunosa won’t flower, or only produces one or two blossoms instead of a cascade of richly scented flowers.

There are a couple of things that could be preventing your plant from flowering, and fortunately, both are usually relatively easy fixes!

Firstly, check whether your plant needs more nutrients in its soil. You can add an organic fertilizer or any balanced orchid mix to its pot. Increasing the amount of nutrients available should help to give the plant a boost and get it back into flowering. Don’t overdo it, though! Remember, too little food is better than too much.

Secondly, check the light conditions. Hoya lacunosa plants struggle to flower in low light, and will usually devote most of their energy to making leaves instead. To encourage your Hoya lacunosa to flower, try and slightly increase the amount of light it is being exposed to.

Don’t take this to mean you should dump your plant in full sun – it won’t like it. Simply move it a few inches closer to a window if you can, pull back a blind if one is blocking its light, or consider adding a grow lamp to give it a boost if there isn’t much natural light available.

One or both of these strategies will hopefully overcome the issue and help your Hoya lacunosa start producing flowers!

Why Are My Plant’s Leaves Dull/Discolored?

Foliage that is the wrong color or has turned very dull is usually a sign that your plant isn’t getting as much food as it needs. It will usually also grow very slowly if this is the case, so you may feel like it’s not getting any bigger.

The best solution is to fertilize it (gently) over the course of a few months and see if it picks up. You can also use rainwater to humidify (just add it to the tray or spray bottle) as this will contain nutrients that will run into the soil for the plant to pick up. In the natural world, Hoya lacunosa plants depend on rainwater for nutrients.

Watering your plant with rainwater is another good way to help them when they are looking a little sickly.

Why Is My Hoya Lacunosa Very Limp?

Limp leaves are a sign of a problem in most plants, and the Hoya lacunosa is no exception to that. It should not look limp.

Usually, limpness is due to watering – either too much or too little. In the Hoya lacunosa’s case, it will usually be too much, since they are pretty drought hardy and most people over-water their houseplants.

Check whether the soil is damp and whether you are watering it too often. Watering your Hoya lacunosa too much will lead to root rot, which will kill the plant. If you are worried that this has happened, take the plant out and check its roots for mushiness.

If the plant’s roots have turned soft and wet, cut away all the damaged roots with clean, sharp scissors. Repot the plant in fresh, drier growing medium, and reduce the amount of water that you give it.

Root rot is not something to be taken lightly; it will kill your plant fast, because your plant won’t be able to take in either nutrients or water, even if both are readily available.