It was at least 10-12 years ago when I first tried with this Hoya; back then it was called Hoya sp. Biak Island. It was a lovely plant with silver splotches on the leaf surfaces, but it only did well in my outdoor greenhouse and I lost my plant within the first year. I was determined to find another at a future date. I finally had a chance to obtain a cutting of Hoya collina in September of 2017 from AH Hoyas; at that time it was called Hoya biakensis. It was part of a disastrous order where 8 of the 12 plants that I ordered arrived dead. Hoya collina was just barely hanging on, but with a lot of TLC, I manage to save it from the brink. Considering the hell it put me through later on, it might have been better if it had not lived!
This Hoya started out fairly strongly and grew pretty well over its first winter with very few leaves getting the frosted color of my first specimen. I repotted regularly and my plant grew into a sizable specimen. It all started to go downhill during the winter of 2018/2019 when leaves started rapidly yellowing and I was continually pulling them off, because if there is one thing I hate is yellow leaves on a Hoya! I probably lost 20 percent of the leaves that winter.
The plant picked up during the summer of 2019 growing many new leaves in the summer greenhouse. So I decided to keep it around and hope for a better winter with it, but it was not to be! The winter of 2019/2020 was every bit as bad and maybe worse than the previous winter. I tried everything I could think of but I kept having to pull off yellowed sickly leaves. I so wanted to throw out this plant, but I had put so much time into it, I wanted to flower it before it went away. Hoya collina gave me such a miserable time, that in my mind, I thought that I had owned it much longer than I actually had. I believed it to be 5 or 6 years when in reality it had only been a little over three when, in 2020, I added this plant to my Hoya Hall of Shame. This was a designation that I gave to a group of Hoyas that had resisted all of my efforts to flower after many years.
To add insult to injury, in early May of 2020, I discovered a peduncle with tiny buds on the plant after bringing it outside for the year. The temperatures at that time were so cold and erratic that I lost the buds. If I had seen them first, I never would have brought the plant outside until after it had flowered. In hindsight, it may have been a good thing that I discovered that peduncle, which eventually yellowed and fell off. If I had not found it, I probably would have tossed the plant that summer and not had a chance to see it flower.
When I brought the plants inside in the fall, I put Hoya collina back in the grow tent with the hopes that by spring I would see flowers. I put it in a very bright spot under LED lights, and increased the watering as it seemed that letting it go dry increased the plants propensity to get yellowed leaves. It was the plants last chance to flower, as I was determined to throw it out. It was checked fairly frequently for peduncles and finally stumbled upon one in December of 2020. It flowered 3 weeks later. I was on top of the moon, and was so happy to get this albatross off from around my neck!
Hoya collina Is Endemic To Biak Island, Indonesia. The flowers last around a week; they drip small amounts of nectar and smell lightly of butterscotch. Because of my bad growing history with this plant, I cannot say that it is one of my favorite Hoyas, nor give it a recommendation. My experience though may not be your experience, so give it a try, and let me know how you fare. There is nothing better to behold than a Hoya growing nicely in full health, but spending years on a plant that just won’t grow properly can really sour you on it!