It happens to my miniphals, I assumed it had to do with a high amount of sun, but not enough to burn them.
The new leaf seems to have a reddish tint (if I am looking at it correctly) which could be consistent with anthocyanins that a red/purple phal produces to protect itself from the sun. It's an adaptation to prevent the plant from burning, but you can see it as a hint to move it out of the sun. (I think of it as an orchid getting a tan, haha xD)
As far as I know, once it's become like that, it's pretty much changed permanently. However, the reddish tint does fade after a while once the orchid is no longer in so much light. (But it never completely goes away.)
My orchids grow well otherwise, so it was not something I thought to worry about!
|