Today's Gardener (todaysgardener.com) participates in the Amazon Services LLC Associates Program.
Hoya Obscura is distinguished from other species of the Hoya genus by its glossy, wax-like, veined leaves that can assume tinges of deep bronze-red under certain circumstances. Not all plants exhibit this tendency though. This plant is an epiphyte native to the Philippines, with compact bushy growth and a mild fragrance.
Care basics: As a Philippine species, it loves moisture, humidity, and bright indirect sunlight. Occasional baths will make the plant happy. Never let it dry out completely since it withers when too long in such condition. However, it does not like constantly moist roots, either. Let the soil dry about 2 cm and then apply water. It appears to be almost immune to pets such as mealybugs and aphids which are not fond of it and will leave it for a more appetizing plant, so you won’t have to worry about them. However, be watchful of snails if you keep the plant outdoors.
These are the topics we shall go through:
- Introducing Hoya Obscura
- Where can you grow Hoya Obscura?
- What type of light is ideal for Hoya Obscura?
- Any specific humidity requirements?
- More on Hoya Obscura temperature
- Does it require any special type of soil?
- How often do you need to water Hoya Obscura?
- Potting and repotting essentials
- How important is fertilization?
- Does it need pruning?
- How to propagate Hoya Obscura using different methods?
- Pests and common issues + simple fixes
- Care tips in a nutshell
Continue reading to learn the information you need to take tender care of Hoya Obscura!
Introducing Hoya Obscura
Before we get down to analyzing the basic steps of care of this member of the Hoya genus, let’s discuss the visuals. First of all, learn how to recognize its foliage and inflorescence.
The leaves are glossy, wax-like, excessively and conspicuously veined. Though they can vary in size, the shape remains the same. Once they are established and begin to grow, they enlarge and become much thinner, and assume a lighter green color.
When given more light or fertilizers that contain a high concentration of phosphorous, they can turn deep red-bronze color on the leaf blade or the edges. The veins remain green, which contrasts beautifully with red. Some clones tend to exhibit such tendencies, but not all varieties.
The clusters of flowers are flat and dropping down. They consist of dainty, fuzzy, cream to pink-colored fluffy balls (corollas) and a cream-colored corona.
Pedicels and buds that haven’t opened exhibit deep pink around each flower. The cream-colored crystals (coronas) will appear at the tip of the still pink corolla briefly and that means that the flower is fully formed.
Before dropping, flowers will turn completely yellow, which signifies saying a temporary goodbye. They have a lovely fragrance, sweet, but not overpowering.
Now, does Hoya Obscura remind you of another plant in the Hoya genus? The answer is Hoya lacunosa.
If you compare it to Hoya lacunosa, you will find striking similarities, so we can say that these two are relatives. They closely resemble one another because they are both specimens in the Otostemma section.
They both have a fuzzy ball with a star in the center that looks like a crystal. However, this fuzzy ball exhibits pinkish color in the case of Hoya Obscura and the corona is cream-colored rather than yellow. Also, its foliage can develop excessive tinges of red, which is a tendency Hoya lacunosa doesn’t display.
Hopefully, now you will be able to distinguish between the two when you happen to come across them.
Where Can You Grow Hoya Obscura?
One effective way to display it is by rooting it on coconuts. It can be pinned circularly around the husk which is then hung from a wire hooked into the coconut. Since not many of us have coconuts, you can use any hanging basket and it will attract everyone’s attention nevertheless.
Before I give you a comprehensive care guide on each of the sections (light, watering, fertilizing, etc), allow me to introduce you to other members of the astonishing Hoya family:
What Type of Light Is Ideal for Hoya Obscura?
Positioning your plants in an adequate spot is of utmost importance because plants produce their nutrients in connection with the sun.
Determining the amount of sunlight needed is not always easy, but you can learn by trial and error. This is especially problematic in the case of hanging basket plants that receive less sun than those placed on the windowsill.
This particular species should be provided with indirect exposure to sunlight at least half a day. West-facing windows can be quite hot in the late afternoon, so make sure you don’t put the plant too close to it. Moreover, try to protect the plant with the presence of some other plants or curtains.
So, bathing your plant in the morning sun by the east-facing window is ideal.
If your plant is receiving less sun than it should, new growth will be smaller in size and paler, and it might stretch towards the sun. On the other hand, if it is receiving too much sun, sunburn may occur or even wilting.
Like I said, trial and error. Observe how the plant is reacting to different light conditions, and modify accordingly.
Any Specific Humidity Requirements?
Humidity levels vary from household to household and certain types of plants require different humidity levels. Broadly speaking, household humidity is sufficient for most houseplants, but there are cases when you will have to increase humidity and make the air less dry.
In the case of Hoya Obscura, humidity levels should be between 40 and 60 percent. To increase the amount, what you can do is create a tray of pebbles, line the container with moist sphagnum moss, or buy a humidifier.
More on Hoya Obscura Temperature
Every plant has an ideal temperature range in which it prefers to grow as well as a wider one that it can tolerate.
As for Hoya Obscura, the ideal temperature in the summertime is around 30 degrees C, while it can tolerate even higher temperatures than this. On the other hand, the room temperature in the winter season should be kept between 10 and 15 degrees C.
If you cultivate your Hoya Obscura in the basement or in the attic where it is more difficult to maintain warmer temperatures, you can install heating systems and provide sources of additional light.
When the period of dormancy comes, however, move the plant into a cooler room so that it can rest before the new growing season. In case you are cultivating Hoya Obscura outdoors, make sure to bring it indoors when temperatures drop below 10 degrees C.
Does It Require Any Special Type of Soil?
Well-draining, well-aerated, porous, and slightly chunky growing medium are essential for growing a healthy Hoya Obscura with the minimized risk of root rot and other issues.
You can use any good quality mix for indoor plants. To tailor the soil mix to the plant, various substances can be added to the basic potting mix.
For instance, you can use orchid bark and perlite to allow more air into the soil and speed up drainage. Furthermore, you can add horticultural charcoal to absorb waste and keep the soil fresh. Sphagnum moss can be placed over the surface of the plant to retain moisture.
The medium for indoor use has to be sterile, pH neutral, or mildly acidic (6-7.5) and firm to support the plant, but lightweight enough to hold the air and supply the plant with water and nutrients without waterlogging.
How Often Do You Need to Water Hoya Obscura?
Experience is the key to successful watering but in the meantime, what you can do is plan your watering routine strategically and deal with problems quickly and effectively. The golden rule to remember here is never to let this plant dry out completely and make sure not to overwater it. Balance is crucial.
It needs to be moist, but not soaking wet or waterlogged. Since it has waxy, somewhat succulent leaves, it reduces moisture loss. You can assess other situations and reach a sound decision. Here are a couple of useful hints for you:
Water more frequently in the following situations:
- In summer and spring when it is the growing season
- If the plant is located beside the hot window
- In case the air is drier
- Before repotting
- If the leaves fade and fall off quickly
Water less frequently in these scenarios:
- When the plant is resting during the winter months
- If it grows in humid and cool conditions
- In case you have repotted it recently
Check the moisture level once a week. Using a water indicator can help with that since it changes colors when the soil is dry, indicating that it needs more water. Or you can simply use the index finger test.
Using rainwater is the preferred type of water. But, in case you cannot collect it, there’s distilled water or tap water BUT on only if you leave it be overnight.
Potting and Repotting Essentials
It is not a novel insight that Hoya plants don’t like to be repotted frequently. In fact, they prefer to stay slightly root-bound and be repotted only when necessary, as in the case of root rot, outgrowing the original pot, being infected by pests, and other diseases.
You can keep your plant in a nursery pot if it is a young plant, but if you get a mature plant, inquire how long it has been living in the current pot. If more than two years and you notice that the soil does not drain well and it is too compact, then it is time to repot.
Before planting Hoya Obscura in a pot, you can put crockery shards like stones and pieces of broken clay on the bottom of an empty container to help speed up drainage. This is effective for all plants that can’t bear to sit in the wet soil for any length of time.
Replace the old soil, use fresh and rich potting mix. Plus, apply some fertilizer in poor concentrations. Water less frequently and provide bright indirect sunlight to partial shade to allow the plant to recover from the shock of being repotted.
How Important Is Fertilization?
As an epiphytic plant, Hoya Obscura absorbs nutrients through air, rain, and less so from the growing medium. Regardless of that fact, you can still supplement your potting mix with a balanced, preferably organic fertilizer once a month during the growing season. I’ve already hinted what happens when you use the one which is richer in phosphorus.
In case you are using synthetic fertilizer, cut the strength of it by half of the recommended one provided in the directions. You can use a liquid fertilizer too which is absorbed more quickly than a solid one. One of the options is to water the plant with it, the other is to mist the leaves. On the other hand, solid fertilizers are added when repotting or on the surface of the plant.
In case you have just got your plant, it is best to fertilize it as soon as possible. That’s because you won’t do so for at least two weeks before leaving the nursery.
Does it Need Pruning?
The best time for pruning is in the spring when the plant is growing and new growth will respond more quickly. To prune, use clean, sterilized shears or a knife. Use gloves in case white latex appear. Avoid cutting any stems that have spurs on them since new blooms will appear again. Rather, cut below the node on the stem, making sure to do that from the right angle.
How to Propagate Hoya Obscura Using Different Methods?
Do you want to have more Hoya Obscura plants? If yes, then consider propagating the plant.
The first factor to determine is the period when you should propagate. Ideally, do it in the spring when the plant is actively growing and it will recover more quickly.
The second question to answer is what the best way to propagate Hoya Obscura is. Well, there are a few.
#1 Root cuttings
Simply cut some of the roots, place them in a pot with drainage holes, and rich growing medium and water moderately. The disadvantage of this method is that it can only be done when repotting. Repotting for propagation solely is not advisable.
#2 Stem cuttings
These are the 6 steps to follow if you use stem cuttings.
- To propagate, use clean and sterilized garden shears.
- Take at least 5-inch cuttings, cut them just below a node.
- Next, you should remove some of the lower leaves on the cutting.
- Thirdly, choose a rooting medium, either liquid or solid. In case you opt for water, place the cutting vertically in a jar of water, making sure that it does not fall. The solid one can be soil or sphagnum moss. The medium should be kept moist, not wet.
- For plants that have a difficult time rooting, the addition of rooting hormones is advisable, either in a solid or liquid form. Dip only the end of the cutting in the powder, tap off any surplus, and put it in your preferred rooting medium.
- As soon as the roots appear, transfer the cutting into the soil and plant as per usual.
#3 Growing from seeds
Plants grown from seeds can bear characteristics of ancestors going back several generations, which is not the case with cuttings. However, this method remains the least used one.
To propagate successfully from seeds, be guided by the instructions on the seed packet regarding the depth at which it should be planted and whether it should be covered or not.
Sowing too deep is not recommended because it will run out of energy before it reaches the surface. Bear in mind that fine seeds don’t need much coverage.
Here are 4 simple steps to take:
- Sieve a fine layer of silver sand or any soil over the top of a pot or a seed tray.
- Sprinkle pinches of seed over it and hand-mix slightly so that the seeds can be seen.
- Cover the pot with a plastic bag.
- Place it in a shady spot of approximately 15 to 20 degrees C. In case you are using a tray, put it inside a larger one containing water.
Pests and Common Issues + Simple Fixes
By far the majority of pests are brought into the home on new plants. To reduce the risk to the minimum, buy plants from a reputable outlet where the plants have been properly taken care of.
To begin with, ants are a lot more of a problem outdoors than indoors. They can become a nuisance in the conservatory, tunneling alongside roots, and join aphids because of the sweet honeydew they produce.
If they are annoying to you, try getting rid of them, but be ready to have a persistent and constant battle with them. One of the ways is to dust any ant killer or use a systemic insecticide pin. Some people prefer to let their Hoya Obscura be the home for ants and reap the benefits ants provide the plant with in return.
Other insects that can occur are mealybugs manifested in form of dust. Simply dap your cotton swab in alcohol and thoroughly clean the crevices of the leaves.
If the air is dry, spider mites can appear too. Use insecticidal sprays outdoors to get rid of them. Do not forget to isolate the infected plant to prevent other plants from becoming infected.
In some cases, you will have to remove parts of the plant, and sometimes the plant cannot be saved, as in the case of a virus when the plant cells change and this is manifested in yellowing or mottling of leaves.
Care Tips in A Nutshell
Hoya Obscura responds favorably both to indoor and outdoor cultivation provided that the basic requirements are met. These include:
- Providing conditions necessary for the process of photosynthesis: warm and humid environment with adequate sunlight and proper watering routine
- Well-draining and porous potting mixture
- Judicious fertilizing
- Pruning at a distance from the spurs or buds
- Keeping an eye for pests and other diseases
At first glance, it seems that Hoya Obscura is a high-maintenance plant. Many are discouraged from cultivating it because of the ants it tends to attract. But if you like challenges and are an avid collector of Hoya plants, definitely give this one a try. There is not one person who doesn’t enjoy the appearance and the smell of its lovely flowers and luxuriant, glossy, green to deep-bronze leaves.
Which is your favorite propagation method for Hoya Obscura? Hit the comments section below, I’d like to hear from you!