I attended a seminar by Dr. Robert Halgren on growing orchids under LED lights. From his web site these links will send you to his Utube home made videos, cute but What I find interresting is the color of his plants growing under LED light. Now watching his Utube video there were other same subject videos to watch on growing under LED light. what I find interresting the environmental growing conditions changed because LED's dont produce heat and they talk about that condition.
http://www.littlefrogfarm.com/ is the home page for Dr. Robert
Some videos: Not the highest production quality, and I narrate like I teach - completely on the fly. If you can get over that, there is some good
information in here.
On a side note: This is very interresting
http://www.youtube.com/watch?v=xJIjJ5nZUZw growing with LED's LOL