Hoya linearis is widely regarded by Hoya enthusiasts as one of the most difficult Hoyas to grow, and I agree 100 percent! I no longer grow it, but would like to play around with it again. It is a really cool looking plant with a very long lasting flower, but keeping it alive is a real challenge that few can seem to master. I think it likes it very dry, and I have trouble with that. It will flower at a very young age from cuttings. Try this one at your own risk!
Ten years later I am trying Hoya linearis one more time, because of the kindness of one of my YouTube subscribers. She sent me a small plant for me to give another go and so far it has exceeded my expectations. When I received the plant my first shock was the medium in which it was growing. She was growing the plant in what looked to me like bonsai soil. I emailed her to ask what it was, and she said that it was indeed bonsai soil made by a company called Bonsai Jack. She used it she said because she was too kind to her plants, which I interpreted as she watered frequently and this medium was insurance against root rot.
I was intrigued by the mix; as everyone knows, I am a notorious over-waterer myself. I ordered up a bag to experiment with other Hoyas and to have on hand for transplanting my little linearis plant if I was lucky enough to have it grow for me. The problem that I found with the bonsai mix was that it was very difficult to tell when to water. The mix is hard, sharp and difficult or impossible to put your finger into to test for dampness. It is also heavy, which throws off my ability to test for dryness, by hefting the pot. It seemed that water pretty much poured right through it, but I settled on a weekly watering routine just by guess work. Watering the little plant once per week seemed to do the trick and the plant was actually growing! By the end of the summer it had roughly tripled in size, and needed repotting. I pulled it out of its 3 inch pot and moved it up to a six inch.
I noticed that as we moved into late September that there was a couple of very small peduncles forming on the ends of two of the vines. That was very exciting as I had not seen or experienced the blooms in over 10 years. By mid October there was very little light in my north facing window where the plant had lived so I opted to move it into one of my cooler growing tents to see if the lights would mature the buds and get them to open. It worked!
The flowers of Hoya linearis smell delightfully of lemon and last for two weeks plus, which is a solid run for a Hoya. The plant is a native of the Himalayan region in Northern India. This is a great plant that I have not been growing long enough to have a firm opinion of its difficulty. I do know that it is considered a cool grower and those plants always seem to present problems for many growers myself included. I will update this blog at the end of the winter after I see how the plant fares. For the time being it will remain in my grow tent unless I start losing leaves.