If you like huge leaf Hoyas, I would like to introduce you to Hoya Glabra (pronounced as GLAY-bruh). It’s one of the giant Hoya that has lush green leaves. This one also belongs to the tender perennial section of houseplants, and it’s a tropical species.
The scientific name for this Hoya is Hoya Glabra Schlechter, which is named after a famous plant collector known as Dr. Schlechter. He mentioned this plant in his book in 1908, so this plant has been around for almost a century.
Like many other Hoyas, this plant also originates from South East Asia. It specifically comes from Borneo Island. For this reason, it is sometimes called Hoya Glabra Borneo. It is found growing in moist mangrove forests.
Every gardening enthusiast is in search of a new houseplant to adorn their indoor garden. This flowering plant perfectly falls in the category of must-have houseplants. The rose-colored blooms add a bright touch to this classic green houseplant.
This is a rare annual plant that is great for container gardening. My plant care guide discusses all the instructions in-depth to help your plant thrive indoors.
- 1 Basic Plant Care Instructions for Hoya Glabra
- 2 Common Problems for Hoya Glabra
- 3 Tips for Growing Hoya Glabra
- 4 Frequently Asked Questions about Hoya Glabra
- 5 Conclusion
Basic Plant Care Instructions for Hoya Glabra
This giant plant will grow in a well-draining potting mixture that has orchid and cactus mix with other nutrients. Water it every week in summer but only once every two weeks in winter. The main requirement for this plant is high humidity, i.e., above 60%.
You have to always use a well-draining mix to grow your Hoya Glabra in a pot. Else the roots will be clogged with water. This houseplant appreciates some acidity in its soil; therefore, I would suggest you keep the pH slightly acidic to neutral (6.1 to 7.5).
Another requirement for this plant is that it likes growing in moist soil; therefore, your potting mix should also have good water retention. I would recommend that you prepare your own mix by combining perlite, orchid mix, and cactus mix together in equal parts
Add organic matter to your potting soil. Doing this will increase the nutrient and water retention capacity of your potting mix. This matter will also enhance the overall soil structure and helps the roots penetrate/spread throughout the soil.
Some common products used as organic matter are leaf mold, compost, humus, peat, and manure. Please remember that heavy use of compost can imbalance the quantity of nutrients in the soil.
The best outdoor planting zones for Hoya Glabra are USDA hardiness zone 10a to 11.
With average water needs, you have to water this Hoya plant regularly. You will notice that during the growing season, this plant requires lots of water; this is because the plant is very active and requires water to perform necessary growth processes.
You can water this plant once a week in summer and spring, but in winter, it should be watered once every two weeks only. Mines require water only once a month in winter.
The most disliked thing by Hoya Glabra is overwatering. Therefore always allow the soil to dry well in between watering and water your plant based on the soil condition.
This plant can withstand any environment, from bright sun to partial sun. So you can place it in your window sills or in the corner of your room a few feet away from the window. But always ensure that direct sun never falls on the giant leaves of the Hoya Glabra.
Remember that the Glabra plant has huge leaves, so it requires lots of sun. I have positioned it near my living room window with curtains and filtered sunlight.
Most growers classify this plant as a hot or warm grower. So it will thrive in temperatures from 60 to 85 degrees Fahrenheit (16 to 25 degrees Celsius).
Hoya Glabra does not like temperatures below 57 degrees Fahrenheit (14 degrees Celsius). Therefore bring it inside when the outdoor weather gets very chilly.
Hoya plants are famous for their humidity tolerance, including Hoya Glabra. They can grow in average indoor humidity levels, but most expert gardeners recommend that you keep the humidity higher than 60% for optimum growth.
Plants naturally produce their food using water and sunlight. But as a plant parent, it is your responsibility to ensure your plant receives all necessary nutrients that are provided to it in the natural habitat. Fertilizers are a great option for this.
Apply a balanced fertilizer that has a good ratio of nitrogen, phosphorus, and potassium (1:1:1). Since these three are the major nutrients for a healthy plant system. They play the following roles for your plant:
- Nitrogen is an important component that facilitates the growth of chlorophyll. Nitrogen-based plant food will stimulate green leaves and also encourages the seed development on your Hoya.
- Phosphorus is another essential nutrient for root and flower development. It transfers energy within the plant system.
- Potassium controls many metabolic processes in the plant systems. It is essential for successful photosynthesis.
All three of them are important for plant health for both indoor and outdoor plants.
You might be tempted to add excessive phosphorus content to your soil in order to help your plant bloom prolifically. Be wary that high levels of phosphorus can inhibit the growth of beneficial organisms in the soil.
You should add the phosphorus-based fertilizer only during the blooming phase later switch back to the regular fertilizer.
This plant does not like repotting much; instead, it loves to stay pot-bound. You can repot it after 1 or 2 years only when it has outgrown its container.
Every gardening enthusiast should understand how and why pruning is done. After all, it helps your plant in better growth.
Pruning is a simple and easy way to encourage more growth on Hoya Glabra. Because when you cut back the old stems and leaves, the plant has a natural tendency to develop new branches.
Pruning will encourage new flower spurs and gives a bushier look. You can also prune your favorite Glabra plant for aesthetics. But always take precautions like using sterilized tools and wearing gloves while pruning.
The most common practice to propagate Hoya Glabra is by stem cuttings. I like taking cuttings with two nodes. Leaf nodes are an essential component for propagation because this point is responsible for root growth.
- Perform propagation preferably in the spring or summer season because this is best for the recovery of both the mother plant and the cutting.
- You will need a small pot, plastic bag, and pruning shears. Fill your pot with well-draining potting soil with perlite or vermiculite, as discussed in the soil section. You can add sand for additional drainage.
- Water the above mixture well and leave the pot for a few hours. Make sure the soil is well saturated, and no part is dry.
- Separate a healthy stem that has 2 or 3 healthy leaves on it. Make sure you do not include any unhealthy or diseased parts in the cutting. You can do this with the pruning shears.
- The ideal stem length is around 5 inches (13 cm). Remove all the leaves from the lower edge of the stem near the node. You have to ensure that after planting, none of the leaves touch the soil surface.
- Let the cut dry and recover for a few hours. You can dip the nodes in rooting hormone. You can either use the powder form or the liquid form. This step is optional, but I would suggest doing it because it increases the chances of successful rooting.
- Water the soil regularly because moisture is necessary for root formation. But stay away from overwatering because this will rot your cutting, and you will end up with a failed propagation.
- Another requirement for root formation is light. Make sure you keep this tiny pot in a bright spot with indirect light. Direct sunlight should be avoided because it can bake the young cutting, but I would suggest morning sun because the intensity of light is low.
- Maintain the above conditions and wait for your plant to start rooting. You can use a plastic bag with some holes to create a high humidity environment. Since humidity also plays an important role in propagation.
- It can take a few weeks to a month to root, depending on the environment you provide.
The blooms on Hoya Glabra vary in hues of pink and mauve. The tiny flowers have a bright yellow center. These flowers are small but thick with a star-shaped and off white edge. The flowers shine very brightly when the sunlight falls on them.
The blooms are very tiny, about ½ inches in size; however, each umbel features 15 to 20 flowers creating a pink ball of tiny flowers.
On top of the beautiful color, the flowers on Hoya Glabra also have a mild, sweet fragrance with a hint of citrus.
The next attractive feature of this plant is the huge leaves that have a smooth surface with a velvety texture. The leaves have a fuzzy appearance.
This plant produces long vines that grow large leaves. These leaves can reach about 8 inches (20 cm) in width and 11 inches (27 cm) in length, making this Hoya a great completion for Hoya Pentaphlebia.
Initially, it takes some time to develop the large leaves, but once the root system is established, the leaves can easily grow to a size of 6 inches (15 cm) on average.
The broad leaves have an outstanding waxy appearance for which Hoyas are famous. You will also notice slightly raised green veins on the upper side of the leaves. The veins on the underside are deep purple.
If you grow Hoya Glabra in an outdoor garden or patio, it can get 8-10 feet (2.4 to 3m) high.
Hoya species go semi-dormant in winter. This happens because of the drop in temperature and low light intensity. This is true only for varieties depending on sunlight. The plant will show no sign of growth under these conditions; therefore, it is believed the Hoya is dormant.
If yours is growing in good artificial light with consistent temperature, it will continue growing and blooming even in the winter months.
Winter might be a difficult season for some houseplants because they get less sunlight and temperature. Follow the following steps to help your Glabra plant survive through the cold winter weather:
- Most people easily end up overwatering their indoor plants in winter. We have to understand that the plant is getting less sun and temperature compared to summer. So you cannot follow a watering schedule applicable for the summer season. You have to let the soil get dry completely before adding any moisture.
- Drain the saucer/tray to remove the extra water. Check your plant tray after about 15 minutes of watering; this will help you collect and dispose of the extra water.
- Get ready to change the location of your indoor Hoya Glabra plant. The first step is to locate all the spots in your house that receive sunlight during winter. Make sure all the windows are clean from both sides for maximum sunlight. Clean any dust from the leaves, so they have a better chance of absorbing the sun’s rays.
- Use a humidifier to solve the issue of low humidity and dry air.
Tropical plants like Hoya Glabra need warm temperatures to thrive. But maintaining this is a big issue for most growers in winter. During winter months, I bring all my tropical plants inside and keep them near a fireplace or heater to provide all the warmth they need.
Make sure your plant is placed near the heat source, not very close otherwise, there is a chance of burning or scorching the foliage.
Common Problems for Hoya Glabra
Spider mites are extremely destructive pests that are common in greenhouses, indoor and outdoor gardens. These mites are close relatives of scorpions, spiders, and ticks. Hence their physical appearance is a combination of all three.
Spider mites feed and live on houseplants in colonies. Their favorite place on evergreen plants is leaf undersides; therefore, always inspect this area for mites infection.
They collectively feed on the plant tissues to suck plant juices. These pests make the plant look dusty and dull. The leaves have visible spots of feeding. If left untreated, the leaves will eventually turn yellow and fall off.
To control spider mites, do the following:
- Prune the infected leaves, stems, or any other part that has white webs.
- Wash your infected plant with clean water to force the pests to leave the plant.
- Increase humidity because low humidity will encourage the spread of spider mites.
- Apply organic insecticide sprays.
Dull Looking Plant
There are several reasons for the dull appearance of your plant. One of the basic and most common ones is the natural aging of the plant. If your Hoya leaves have lost their glossy appearance, check the following reasons:
- You recently let your plant over dry to the point it starts wilting.
- You have overwatered your plant, and it remained wet for too long that it fell prey to root-rot.
- You are exposing your plant to very low humidity levels, possibly lower than 40%. Low humidity for very long periods is a death sentence for tropical plants.
- Your plant is suffering from temperature fluctuations. You are exposing it to very hot or cold weather.
- Your plant is infested with pests like mealybugs, spider mites, or thrips.
In simple words, anything that impacts your plant’s root will definitely affect its appearance and foliage.
Tips for Growing Hoya Glabra
- You can add a bloom booster to help your plant have more blooms.
- Go for a pot with at least one drainage hole
- Repot this perennial every one or two years.
- Flush the soil regularly to get rid of salt buildups.
Frequently Asked Questions about Hoya Glabra
I was gifted a few seeds of Hoya Glabra by a friend, can I store them for the next season to propagate?
I would suggest sowing them as soon as possible because the seeds for this plant do not store very well.
Summer is almost over, why hasn’t my Hoya Glabra bloomed?
Hoya blooms are a major concern for most growers since the majority of us cultivate this plant for the blooms. Either your plant hasn’t matured to start blooming, or it is not getting adequate sunlight.
Will my Hoya bloom well if I keep it under shade?
Hoyas are very adaptable plants; they can grow in the shade but will have difficulty blooming if grown under full shade. They certainly need some amount of sun to start blooming. Therefore I would not recommend deep shade for growing flowering Hoya species.
Can I hang Hoya Glabra on my balcony?
Initially, my Hoya Glabra had difficulty blooming. Once I potted it in a hanging basket and hung it to a top support rail, my plant kept repeatedly blooming throughout summer. Therefore hanging this plant in an outdoor location is best for blooming.
The Hoya Glabra can brighten up your day with the pink candy-like blooms. This large leaf Hoya will thrive happily in the warm environment of average households. The venation on the leaves creates a sophisticated look for this simple plant.
I would definitely recommend trying this rare plant to admire the huge leaves and the lovely pink blooms.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.