Several months ago I started over my Hoya blashernaezii ssp siariae as it was languishing and not growing. I think I now know the reason for it – the dreaded flat mite! After spraying my entire collection with sulfur, this plant is one of many that has absolutely taken off, and is growing better than at any time. The white spots on the leaves are sulfur residue. Much more on my flat mite experience at a later date!