Over the weekend I noticed some of the leaves on my Den had taken on a faint watermark pattern. It was barely visible and at first, I thought it was a trick of light. By Monday it became noticeable. Two leaves fell off from the new canes.
I took the pictures below on Monday. The flash enhances the contrast in colors and makes the discoloration appear brighter than it was. I couldn't get the pattern to show up without flash photography. But by Wednesday, the leaves now look pretty close to what's in the photos.
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In one of the pictures you can see a section of a can has turned dark.
It now kind of looks like sun burn but not really. The odd thing is that it's been kept outdoors for a few weeks in a shaded area where it would get some light morning sun. Surely, the sunburn would have appeared sooner. I haven't repotted it, since I purchased it in Feb. The only thing I did to it was trim two spikes that were done blooming.
I don't know what to make of this. Help.