Hoya tsangii was first collected by Daniel Edward Elmer in August of 1912. He found it in the Philippines, Mindanao Island, Agusan del Norte, Cabadbaran (Mt Urdaneta). Unfortunately, he labeled it incorrectly as Hoya angustifolia an invalid name. This was only the beginning of the confusion with the taxonomy of this species. At one time or another it has been called Hoya burtoniae, Hoya odetteae, and Hoya sp. aff. burtoniae. These are all incorrect; this plant belonging to the Acanthostemma Section of Hoya, with the little yellow flowers, is now definitively known Hoya tsangii. A big shout out to Mary Caroll for providing me with much of this research!

Hoya tsangii was given to me as a small cutting by my friend Wil in the summer of 2022. It rooted quickly in coconut husk chips, but for some time was a very slow grower. Eventually it started growing much quicker and went through a couple of up-pottings eventually ending up in a five inch clear orchid pot. This Hoya was not a quick bloomer that would flower withing a few months from a cutting. I was beginning to wonder if it was ever going to bloom, but right around the two year mark it put out its first peduncle and began to bud up. It was one of those rare Hoyas that open its flowers in the day light, and do not open them in the dark. The flowers opened over the course of three days; first two flowers, then six flowers and finally nine flowers.

Unlike most Acanthostemma Section Hoya, this species flowers did not have a strong scent of caramel. The scent was light, fresh and almost imperceptible. The flowers are very small as can be seen in this photo comparing the entire umbel with a quarter for perspective.

If it were to do over again, I would grow this species in a hanging basket. It does not twine, is a rampant grower once it gets going, and is difficult to keep up with tying to a trellis. This plant would also do best where it could actually get less light. My grow tents are over lit and many species get sun stressed and Hoya tsangii is one of them. The leaves get red and blotchy from too much light. I believe they look best when kept nice and green.

This is an interesting plant that has been around in the hobby since the early 2000’s. I wanted to grow it the first time that I saw its cute little yellow flowers, and am super happy that I got the chance give it a go. I don’t have anything bad to say about this plant; the flowers collect a little nectar, but not enough to drip. It is an easy grower that I think could make a somewhat unkept, but impressive looking hanging basket. If you have not tried this one yet I urge you to pick one up. I should also say that a very attractive variegated version has now been released that is quite striking.