my dark green phals are getting light green edges
 

here in the last fer days a couple of my phals are getting light green edges and I can't figure it out I think they all seem to be happy so It must be something I'm doing could some help me out here. Thanks alot

This happened to one of my large white phal.
I had it for a number of years and the leaves were green all throughout, but last year, some of the leaves developed this yellowish line along the edge of them.
I posted a question and no one really knew what it was.

I'm interested to see anyone knows what this is, other than guesses.

Looks to be sporting semi variegated to me.

Some plants have variegation as a defense mimicking poor health, and gets attacked less. No idea if this is the cause with this plant.

I'm definitely no expert, but I think it might be due to light levels. My phals respond to stronger light by developing that light edge. If I lower the light levels, the light edge darkens up again with time.

It looks rather pretty.

Hmmm interesting because the one I had that developed this white edge, was the one that received the lowest light.

All others were much closer to the window and none of them exhibited this.

Let me throw this out for consideration - it is NOT a statement of fact or expression of first-hand knowledge:

The plant looks like it is being grown more dryly than it probably prefers, and I suspect the %RH is reduced this time of year. Together, it could be that the plant is desiccating to a minor degree, and that is appearing as yellowing of the leaf edges - the part of the plant that had the least "meat" behind it, to keep it well-supplied.

I agree with Ray. I have a mini phal that had taken some abuse and responded very similarly, my fault of course. Here's a pic of the edge oldest leaf. I've corrected the conditions and the newer leaves are normal. http://img.tapatalk.com/d/13/12/18/uzy6uhas.jpg

We have been discussing it last year- mine had the same Problem-after reading up on it a bit- it seems to be a Magnesium deficiency-so i add extra Magnesium now and the Leafs are better.

I think there very happy my humid. stays between 65 and 75 they are all watered 2x wk with reg. seaweed and magnesium and I keep my light around 1200fc so if someone thinks I'm doing something wrong please let me know because I dont have a clue whats up thinks agine