Hoya Australis also known as a wax or porcelain flower due to the appearance of the flowers and leaves is a great choice for beginners and has gained popularity as a commonly sought-after houseplant.
Besides the luscious foliage, this plant grows clusters of sweetly scented pink and white flowers. As a climbing plant, it can grow quite high if left untrimmed.
Although the hoya australis is a popular indoor plant, it can be found outdoors in rainforests near rocky terrain. While it is primarily referred to as the Hoya Australis, it is sometimes referred to as the honey plant or wax vine.
Below we have provided you with a guide full of care tips that will encourage the growth of your Hoya Australis.
As a plant that is easy to maintain, the Hoya Australis isn’t demanding in its requirements. In fact, it is rather tolerant to neglect. Of course, we aren’t implying that you abandon your plant but caring for it isn’t going to consume a lot of your time.
A Hoya Australis will grow best when exposed to bright but indirect, filtered sunlight. During the early morning or late afternoon, the plant can be placed in the sun, however, over-exposure can lead to scorched and damaged leaves.
Your plant will thrive when provided with an equal balance of filtered sunlight and shade so it should be positioned near a window away from direct sun.
A plant that isn’t exposed to enough sunlight will struggle to grow to its full potential. If you wish to introduce this plant to your office environment you will be pleased to know that it grows well under artificial lighting too.
Hoya Australis requires an aerated, fast-draining soil that will encourage the plant to grow and thrive.
You can create your own mixture which consists of peat-free compost, orchid bark, and coarse perlite, however, you will often find it mounted on wood and wrapped in Sphagnum, particularly when used for interior decorative purposes however due to the lack of substrate, the plant will require frequent watering.
The potting mixture should have a mildly acidic to neutral Ph and the soil requirements will differ depending on where it is to be kept. For example, if the plant is going to be kept inside a greenhouse it will benefit from a loom-based mixture comprised of bark, sand, and leaf mold, all of which are added in equal quantities.
It is important to select a well-draining mixture to avoid the plant sitting in water. Likewise, if the plant receives an inadequate amount of water, it will die out before regrowing.
Hoyas don’t cope well in colder climates and because of this, a plant that is kept outdoors during the warmer months should be brought inside when the colder months hit.
Hoyas enjoy temperatures within the range of 65 to 75 degrees Fahrenheit. Temperatures that drop below 50 degrees Fahrenheit can cause the plant to become damaged due to the cold.
Avoid draughts, extreme temperatures, and any sudden changes in the temperature because they can all harm the growth of the plant. When left in their natural habitats, hoyas australis cope during the cooler months.
As a succulent plant, a hoya australis tends to store water and doesn’t require heavy watering. A well-draining soil mix will ensure that it doesn’t hold too much water.
You must allow the top half of the plant pot to dry out before watering it. Apply water until the plant is saturated and allow it to drain thoroughly before watering it again.
The plant’s water requirements will differ depending on the season. In the summer it will need to be watered more frequently following the same principle of allowing it time to dry out.
In the winter it will not need to be watered as often. Avoid over watering the plant as this can lead to discoloration and too much water can eventually kill the plant. Though it may seem bizarre, it is better to underwater the plant rather than overwatering it as it prefers to have drier roots.
Despite being a plant with tropical origins, the conditions of the indoor environment where they are now often found are rather different, however, if possible you should attempt to mirror the conditions of a tropical environment as hoyas prefer high levels of humidity.
Although they will cope in less humidity, they tend to fare better in moderate to higher levels. Positioning the plant pot onto a moist container will help maintain a humid environment. Alternatively, you can invest in a humidifier, which will create a humid environment.
During the summer months, a hoya australis will benefit from the application of a general purpose fertilizer. It doesn’t require a hefty amount of feeding so the mixture can be added to water before being applied.
The guidelines of the fertilizer will inform you on how it is to be used. While the use of fertilizer can benefit growth in the summer, it isn’t required during the winter. You may also wish to use additional supplements such as bloom blisters or nutritional solutions which will encourage plant growth.
Hoya Australis are pretty resistant to pests but just like many other plants, you will sometimes find small bugs on the leaves especially if kept outdoors. Aphids are the most common type that you are likely to discover.
Whiteflies are another species of small insects that are known to target Hoya australis, particularly when kept indoors. This is due to the sweet latex sap that disperses from the plant.
The infestations of these insects tend to become more severe during the summer when their populations are rife. The appeal of the sap will attract these flies who will then grow suck on the leaves. There are insecticide products that can be applied to the leaves surface to eradicate severe infestations.
If left untrimmed, your hoya australis can grow large becoming difficult to tame. For this reason, you will likely need to prune your plant. Doing so will maintain the bushy appearance ensuring that it doesn’t get too wild.
Although there isn’t a particular time when the plant should be pruned, Spring is an ideal season because the plant will have finished flowering. Any brown stems or leaves that appear dead can be trimmed as they are likely to fall off soon anyway. If your plant has vigorous stems they can be trimmed back to the node or you may wish to allow them to grow out.
Cut the stems using shears. Avoid over-pruning because this can slow down flowering as blooms develop on new growth. Also, try not to cut the peduncle of the plant as this is where the new growth of the flower emerges.
When cutting the stems you will likely notice a sticky latex dispersing from the stems. Though this is normal if you are pruning the plant indoors it is important to cover any surrounding furniture to prevent it from getting stained.
During the pruning process, you can gather the seeds from the plant that have not yet flourished. Allow the pods to dry out and then sow the seeds as soon as possible.
Propagating a hoya australis is a relatively easy process, but provides a great way of expanding the collection of Hoya plants from the mother plant.
There are two ways to propagate your plant, the first involves soil and the second involves water. If you have just pruned your plant, you can use the cuttings that you collected during the process, however, if not you can take two fresh cuttings from the plant. To propagate the cuttings in soil you will first need to take a healthy cutting of a stem that is not flowering.
Then add the cuttings to a potting mix consisting of perlite and coco peat. Add water when needed and ensure that a humid environment is maintained.
The preferred temperature should exceed 21 degrees. To encourage growth, you may wish to use a rooting hormone. After propagating the cuttings into the soil, you are likely to witness signs of growth within a month.
Alternatively, you may choose to propagate the cuttings in water. Before doing so you will need to prepare a container with filtered water, and then add a rooting hormone which will stimulate the growth of the cuttings. When the container is prepared, you can add your cuttings to the water ensuring that the nodes are submerged.
Ideally, your cutting should have two nodes. You will likely notice the formation of root buds roughly two weeks after putting the cuttings into the water. When the roots have begun to form the cuttings can be transferred into soil where they will continue to develop.
You should avoid repotting your hoya australis until you are left with no other option other than to do so. This is because hoya australis do not cope well with root disturbance. If the plant begins to appear overgrown in the pot that it is currently in, you will eventually be faced with the task of repotting it to a larger alternative.
To do so, you will need to ensure that you select the correct size and type of pot. Clay or terracotta is an ideal option as they encourage healthy growth.
Your chosen pot should be designed with holes at the bottom that allows the water to dissipate rather than gather at the base. Also, ensure that the soil in which you insert the plant is well draining as this will prove to be more effective in allowing the moisture to filter through.
A pot and soil mix that doesn’t allow the water to drain can affect the health of the plant, potentially resulting in root rot.
Read about caring for these other popular Hoya varieties:
Hoya Curtisii: Expert Care and Propagation Tips!
Hoya Krimson Princess Majestic Care Tips
Hoya Krimson Queen – Royal Plant Care Complete Guide
Hoya Pubicalyx The Porcelain Flower Plant
Hoya Carnosa Compacta Care Tips You Wish You Knew Earlier
Hoya Australis Symptoms
Some of the following symptoms can help to identify possible issues with your hoya australis which may prevent the healthy growth of the plant.
The sooner these signs are identified, the sooner they can be rectified.
Discoloration of leaves
Discolored leaves are one of the most telling signs that your plant is being exposed to too much sun and the environment isn’t humid enough. As a result, the leaves will become scorched hence why they will begin to turn red.
To rectify this problem you will need to position the plant at an angle where it is not exposed to direct sun. If the leaves are beginning to turn yellow, this may be caused by colder climates. For this reason, it is important to ensure that the correct conditions are maintained.
Wilting and Shriveling leaves
Leaves that appear shriveled and wilting signify a possible water-related issue. It may be that the plant has been underwatered or overwatered.
If the roots have been sitting in waterlogged soil for some time, they may begin to develop root rot. A quick feel of the roots will soon inform you of the issue and you should then alter the watering habits accordingly.
If it is a case of underwatering, you will slowly need to increase the regularity in which the plant is watered. You may also wish to take some cuttings and propagate the plant.
The stems/internodes will appear rather stretched if they aren’t exposed to enough light and this is because they are extending in search of the nearest light source.
To rectify this issue position the plant closer to a light source.
Leaves that are suddenly starting to drop off
Abrupt leaf drops can signify shock caused by cold temperatures. Hoya’s aren’t very receptive to temperatures below 10 degrees celsius. To avoid any problems caused by windchill avoid placing the plant on a windowsill where there is a draft.
Ensure that it is positioned in a warm and humid environment.
Lack Of flowers
If your hoya australis is yet to flower, it is likely due to insufficient exposure to sunlight. If this is the case, you should adjust the position of the flower so it is directed towards a filtered light source.
Also, it is worth noting, that stress tends to stimulate flowering so a brief dry period may encourage growth.
Presence of sticky sap on the leaves
If the hoya appears to have sticky sap on its leaves but is not in flower, it may be caused by sap-sucking insects.
Upon noticing this sap on the leaves you will need to see whether it is due to bugs as you can then act accordingly. Remember to be cautious because this sap can stain clothes and furniture if not dealt with carefully.
If the plant has been overwatered and the soil isn’t well-draining, root rot is likely to develop.
Unfortunately, root rot can be very damaging to the plant, so if this appears to be the problem you should take some cuttings for propagation.
Facts about the Hoya Australis
- The Hoya Australis originates from Eastern Asia and Australia.
- It produces a toxic latex that can be an irritant should it come into contact with the skin. Due to the toxicity of this latex, it should be kept away from children and animals.
- If you have repotted your Hoya Australis, you should not feed it for around 5 to 6 weeks.
- This plant requires medium to high levels of humidity. To maintain this humidity you may mist the plant.
- Although primarily grown inside containers, as a climbing plant it can trail up to 3m in length. For this reason, it can be trained to grow in different outdoor environments.
- The recommended temperature of the environment where the plant is going to be kept should fall in the range of 18 to 24 degrees celsius.
What Are The Different Varieties of Hoya Australis?
There are several subspecies of Hoya australis and although their appearance may vary slightly, overall they tend to produce similar flowers.
We have identified some of these subspecies below, awareness of each will make it easier to identify which subspecies you own.
Hoya Australis Lisa
This subspecies has thin white, dark, and pale green leaves and is one of the rarest subspecies.
It is a slow-growing plant that can be trained to climb. It should be fed fortnightly during the spring and summer.
Hoya Australis Kapaho
This plant has sharper leaves at a young age which then transform into round leaves when the plant reaches maturity.
The leaves have a glossy and smooth appearance and produce beautiful white and pink flowers.
Hoya Australis Grange
Recognized for its larger leaves, the Hoya Australis Grange produces similar white and cream blossom flowers to the other subspecies of this plant.
Hoya Australis Tenuipes
The Hoya Australis Tenuipes blooms during the winter and fall seasons. Deemed to be one of the easiest species to grow, it produces beautiful fragrant flowers which are surrounded by glossy, round leaves.
Just like the previous species, it produces white star-shaped flowers with a red-colored center.
Hoyes Australis Tri-color
This species has oval thick wax leaves which are decorated with splashes of color. Thus including white and pink detailing. In its natural habitat, this plant has crinkly, succulent leaves.
You should expect this plant to flower between 1 to 3 times a year.
Hoya Australis Rupicola
Unlike most other subspecies of the plant, the Hoya australis rupicola is a scrambling plant rather than a climbing plant and has rather long leaves in comparison to other subspecies.
Hoya Australis Oranicola
With oval, red-tinted leaves, the hoya australis oranicola produces sweetly scented flowers and during the winter months, it should be grown dry.
Other subspecies include hoya australis Variegata, australis keysii, australis tonga, australis tenuipes, australis lizard isle.
Problems with disease
Sooty mold tends to be one of the most common types of diseases that are suffered by the majority of hoya plants and this is because of the plant sap that they produce.
Hoya Australis is known to attract Aphids which can cause problems with sooty mold. However, you will be pleased to know that this problem is rather easy to eradicate simply requiring you to wipe over the leaves upon noticing the issue. You may also wish to add diluted fertilizer to the plant too.
Frequently Asked Questions
Are hoya australis rare?
The country in which you are located is going to influence how easy it is to source the plant. It also depends on the subspecies that you are looking for as some will be easier to find than others.
Even if you are struggling to find the plant in your local area, an online browse is likely to prove helpful in locating the plant of your choice.
Are hoya australis hard to care for?
As we have identified, hoya australis are easy to maintain and care for and because of this, they are an ideal choice for those who are new to keeping plants.
So long as their living environment requirements are met, and they are watered correctly, you aren’t likely to endure any problems when keeping your plant.
How much do Hoya australis cost?
The cost of the plant is going to depend on how easy it is to source. If you live in an area where this plant is particularly hard to come by, you are likely to find that when you do find them they are more expensive due to their rarity.
If you live in an area where the plant originates from you aren’t likely to have so many difficulties finding them so they are likely to be cheaper.
How do I ensure that I am successful in propagating my plant?
To ensure that you are successful when propagating your plant, there are some things that you can do. Keeping the cuttings in a sealed environment will enhance the chances of successful root growth, e.g a sealable container.
The humidity of the environment is also going to be highly influential in determining how well the plant grows.
There are many reasons why the hoya australis has gained huge popularity as an indoor houseplant. Not only do they bloom fragrant flowers, but they have a beautiful aesthetic and grow to an impressive height too, hence why many individuals invest in these plants for decorative purposes.
Despite there being numerous subspecies they all tend to have similar requirements when it comes to growing temperature, humidity, soil, and water requirements. Overall, they are a very easy plant to maintain and a worthy addition to your indoor houseplant collection.
The hoya australis is an ideal option for those looking for a plant that is easy to maintain but doesn’t compromise on aesthetic appeal.