| Vandas are mostly warm growing and mostly high light. I generally don't think these are good indoor plants, with maybe the exception of the smaller varieties, those with lots of ascocentrum in them. But, if you are determined to grow the big showy ones, I guess the HPS lights would be the way to go. But, while I grow a lot of Vandas, I do it in a greenhouse, and as yet have very little experience with HPS and flourescents, so may not be the best judge. Cynthia |