I believe that I may be the first person to flower Hoya stenophylla in the U.S. so I am going to lay out my exact conditions for those who want to try to duplicate the feat.

Temperatures at night varied from a low of 59 degrees F to a high of 62 degrees F. The daytime temps varied from a low of 76 F to a high of 80 F. Humidity was always above 75%. The plant received 15 hours of indirect high output LED lighting. By indirect I mean that it did not hang directly under, but just off to the side of a light that was so powerful that it burned holes in the leaves of some of my other Hoyas such as H. icensis.