Leaf Health

[douglas]

The underside of several leaves on one of my Phalaenopsis plants are rutted with lots of little dents that are clustered closely together on a portion of each leaf, and these clusters appear to be growing in size. The leaves look OK from the top sides- it is only the underside that looks sick. It appears as though there is no inner flesh to the leaf where the cluster of dents are. I see no insects anywhere. What is this and how do I prevent it from spreading? The roots are healthy and the plant appears to be healthy otherwise.

New to Orchids
Douglas in Aspen

[orchidlady]

A picture would help, but sounds like cellular collapse and many things can cause that. I am having a little trouble with that on a couple plants right now due to the heat (and lower humidity) we are having this summer. This week is supposed to be mid to upper 90's . Other causes include pests, bacterial, and fungal diseases.

Susan

[JoeW]

Douglas, welcome to the Forum and can you post a picture of what you are seeing? Thanks,

[Brutal_Dreamer]

Could be spider mites also. Is your growing area fairly dry? Again, a photo should help.

Cheers,
BD

[douglas]

One other orchid expert suggested that it is not likely toxicity since it takes longer than a couple months for cell deterioration in the leaves to occor as a result of over fertilization. At any rate, here is a photo of the problem. Perhaps this image will clarify what it is.
If toxicity from overfertilization is the problem, thus cuasing cell breakdown in the leaves, that would be because I water the plant almost daily with a weak 25% strength solution. But in a separate thread here, I have mixed reaction from different folks as to whether or not a weak 25% strength solution could cause this sort of toxicity if used on a daily basis. I water the plant so often because it is potted in non-organic medium of transparent glass stones in a wire basket that allows uninhibited air flow. The roots look great.