As with many Tropical Plants, Hoya care requires consideration of their natural habitat. Drainage Hoyas can be found in most terrestrial habitats known to man. Most Hoyas inhabit tropical regions and enjoy warm, humid conditions for most of the year. For example, many Hoyas originate from Indonesia, which has a tropical climate with average annual temperatures in the region of 30 degrees Celsius. However, even tropical regions show variations in climate, decreasing as you get further inland and at higher elevations. It is much cooler from June through to September when the North Eastern monsoon arrives.
Many Hoyas are epiphytic and share their homes with, or make their homes on, other tropical plants. They establish in the forest canopy, entwined around branches and clinging to bark with their roots. Their only food is the decaying matter found in the crevices, washed over their roots by water run-off.These observations give you an insight into the life of tropical Hoya in their natural habitat. Remember that Hoyas do inhabit an incredibly varied range of habitats and grow in many different ways. However, these observations apply to the majority of Hoya species found in tropical regions. You can provide these conditions by following a few simple steps.
These plants will benefit from excellent drainage. I use a 50/50 mix of compost and Perlite. This gives the roots optimum airy conditions they need and prevents water-logging, which is one of the only ways to kill many Hoya. Hoya tend to inhabit semi-shaded forest canopies – don’t let them sit on a scorching windowsill. Direct sunlight in small doses may be of benefit, but continued direct sun will bleach the leaves and harm your plant. This also applies to most tropical plants. Hoya australis ‘Lisa’ enjoys a bit of strong light. The new leaves are tinged with red in bright light, reverting to their variegated form.
If your potting mix is well-drained, you shouldn’t have a problem with watering. Water when the soil is almost completely dry and you will be allowing plenty of air to the roots. An epiphytic plant will have just enough water to get by on, but not so much that they become waterlogged. To recreate canopy conditions, I mist mine every few days. This also allows me to apply foliar feed, which I do about 4 times in the growing season, and each time a plant is in bloom.
Hoya should not be exposed to temperatures below 10 degrees Celsius for long. If you are over-wintering them in cool conditions, please make sure they are very dry.
Remember that most Hoya are Tropical Plants and whilst many are tough, some have a more demanding nature.