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Hoya is some of the most unique species of plants we can keep in our homes. Their ability to change leaf shape, growth patterns, and blooms based on environments and care is extraordinary. Because of these factors, care for Hoya can differ and create incredible results. If one is exceedingly good at caring for a Hoya they are rewarded by vibrant delicate blooms that have unique scents emulating cinnamon, chocolate, and even lemon. Every one of the available 900 Hoya varieties has unique care requirements and characteristics. This is an overall care guide to get you started but we strongly recommend researching the individual Hoya variety you are caring for after reading this to gain even more insight.
Hoya is among the oldest houseplants cataloged by modern botanists. Discovered in the 1800s by Robert Brown Hoya has continued to amaze and stump researchers. Hoya can be found epiphytically climbing rainforests all the way from Asia to Brazil and Australia. A plant species with incredible characteristics that change depending on conditions can only be truly identified by its unique blooms. Many of the documents surrounding Hoya species have been updated many times over the years due to this confusion and even in the 2000s new Hoya are being discovered. Because of their wide range of origin, Hoya can tolerate a wide range of home conditions and make amazing houseplants.
One thing most Hoya enjoy is as much light as you can possibly give. These plants climb trees to get to as much light as possible. When given a lot of light the foliage can naturally sun stress like a succulent and produce beautiful colorful leaves. The foliage can become vibrant red, pink, purple, or even black. It does depend on the Hoya which colors it will become and in some cases the stem itself can even change colors like with a Hoya Carnosa Crimson Princess. Other Hoya can become very silvery like the Hoya Lacunosa.
Hoya is naturally epiphytic so they do not grow in soil normally. They grow in humid-loving moss and bark along with whatever else has grown stuck in trees and they need aeration to absorb nutrients. A standard potting mix can rot a Hoya and needs to have substrates added to it for aeration. The mixes differ depending on the plant parent, environmental conditions, and specific Hoya. An easy mix to start would be 40% soil mix, 30% perlite, and 30% bark. For a more humid environment, a mix of bark or perlite and sphagnum moss would do well too. These are generalizations for the mass-produced Hoya available. As you collect more rare Hoya the mix may have to change as you learn more about that specific variety.
Letting a Hoya dry out too much can cause dry rot. Hoya can handle drought and are very resilient. They will drop leaves and dry out their vine tips if left to dry too much. Water when the leaves begin to feel less soft and more flexible or when the substrate begins to feel dry to the touch. Be careful of hydrophobic soil preventing your Hoya from soaking up the water it needs. Hoya does not need to be watered often but they do need to absorb a lot of water to hold in their succulent leaves. How frequently you water will depend on your home environment and the substrates you choose for your plant.
Hoya is from the rainforests with an average of 70% humidity. Hoya generally can handle lower humidity than that though. Most of these plants can handle a 40%-85% humidity range. They do better and grow more quickly in a higher humidity but many of them can grow in 40% humidity provided the other conditions are met. The more stressed a Hoya the higher humidity they prefer.
A standard slow-release fertilizer with the minimum recommended amount works well. Because Hoya is epiphytic they are used to absorbing nutrients through their stem, foliage, and aerial roots not through soil roots. Their nutrient requirements are minimal. In addition to the minimal slow-release fertilizer Hoya benefit from a foliar fertilizer spray even sprays labeled for orchids and other epiphytic plants can work very well for Hoya.
Hoya can be propagated through cuttings. A node is needed to produce a new plant however singular leaves can grow roots. Hoya cannot produce a whole new plant from a rooted leaf without a node. A node is necessary despite any rooting. To root a Hoya with a node successfully depends on the Hoya. Many Hoya will root in just water while others need high humidity. We do have an article on propagation boxes and humidity-loving Hoya root best with them. Using sphagnum or perlite for your substrate works well with Hoya. Hoya is slow to root and slower to grow but with patience, you can have a whole new plant.
Hoya is fairly pest resistant. Generally, spider mites and thrips will not attack Hoya. This is a relief for many plant parents. Unfortunately, mealy bugs and scale can find their way into cracks and crevices on a Hoya and make it very sticky, hard-to-remove, homes on your plant. Usually, some rubbing alcohol and a q tip can remove them without issue. The difficulty lies in spotting these pests before they have overtaken your plant. Overall, Hoya is very pest resistant especially when compared to almost any other houseplant species.
When discovering which Hoya you have there can be a lot of confusion. This has been a botanist struggle for centuries. Because a Hoya can live in Asia and look one way and then the same Hoya can grow in Brazil and look completely different there have been many cases of mistaken Hoya identity throughout the years. Some Hoya can have multiple names and be the same Hoya or have been called by another name only a year ago. As researchers comb through history and research Hoya today, more information becomes updated and available regularly. The most accurate way to tell which Hoya you have is by their blooms. No two Hoya varieties have the same blooms so far.
Hoya blooms appear on mature plants or cuttings of very old plants. Hoya can take up to a year to produce new growth and up to 2 years to mature and produce blooms. Also, Hoya blooms grow in little clusters of small stems, commonly referred to in the plant community as peduncles. These stems can produce multiple blooms and grow longer after every bloom. If a Hoya is beginning to bloom be sure not to underwater the plant or it will lose the blooms. The scent of Hoya blooms is unique to the plant and can be affected by environmental conditions such as temperature, humidity, and light. The scent is also strongest at night. So if you smell a bloom in the daytime and its scent is minimal try again after dark. The coloration of the blooms can range from white to yellow and pink to red. Almost looking like candy these vibrant little clusters are well worth the effort and wait.
Hoya can be temperamental about their temperatures. Some Hoya can handle cold well while others just melt in the heat. A balmy 70°f works well for most Hoya. Thinner smaller leaved Hoya like Bella tends to struggle in intense heat and do better in cooler temperatures. It does depend on the Hoya and should be a focus when researching your specific variety. Temperatures can affect growth and blooming so it is worth researching if your Hoya could benefit from a specific temperature long term.
Hoya is an incredible plant and very unique. They are great plants for any plant care skill level. Once the basics are taken care of it can be fun to experiment and see what each Hoya species needs to grace your home with vibrant blooms and amazing scents. Even if you just enjoy the foliage and remove the blooms a Hoya can be very rewarding. With ever-changing foliage, it can be very interesting to see how the leaves change colors and shapes in your home. Though they can be a very confusing species of plant they can also be incredibly rewarding and worthy of your time and space.