Grey Discoloration on Leaves of Mini Phal

[DaniBee]

Hi everyone! I’m new here. I noticed this grey discoloration on a mini Phal of mine, does anyone have any ideas of what this might be? They are in a south facing window with white frosted glass. The grey is more on one side than the other, as shown in the photos, and it is more on the side facing the window. Is it possible this is just mild sunburn? I’m worried it might be a fungus of some kind.

[philiplowrey]

It's hard for me to distinguish the exact color on my computer. Is it actually gray? I'd say the pattern looks like pigmentation from sunlight, but if so it would have a reddish tint

[WaterWitchin]

Same here. What’s going on in the middle? No new leaf? Looks like couple of old spikes and third a dry leaf? Can sort of see red tinge on one picture... back off from window a bit?

[estación seca]

Probably sunburn. Even with frosted glass they don't need to be in a south window. Bright indirect light is best. Get some small Cattleyas for that window and put the Phal on a table nearby.

[SouthPark]

Is the darker colouring always on the side that is facing the frosted window?

If so ----- then it will very likely be linked to the light and/or heat coming from the window.

Also - even if is not anything like fungal or bacterial ------ many growers often recommend orchids have some adequate (even if gentle) air movement in the growing area. That can help cut down on still-air conditions ----- which promotes fungus activity (along with other conditions).

[DaniBee]

I uploaded some more photos, I hope the light is better in these. Yes, the grey is on the side that has been facing the window for a couple weeks now. A small spike started again, so I stopped rotating it to allow that spike to form toward the light. What’s going on in the middle, there were three old spikes, and a leaf in the center that had a crack at the base. It was there when I bought the little guy, and I did not notice. It eventually dried up and I pulled it off. I’m curious to see how a new leaf might start, with all that coming from the middle already. I bought him at a flower shop on sale, he wasn’t in the best shape. I decided to try to nurse him back, and it has done better for me. It’s bloomed a couple times since I got him. Until now, I noticed this discoloration!

[WaterWitchin]

If the discoloration has a reddish tinge, just move it back away from the light further. I still can't tell color from the new pictures, but that's where I would start. If you were rotating it, it makes more sense of the way the leaves are showing discoloration.

With what you've said about middle, just leave it be. When a new leaf is ready, it will find it's way up.

[DaniBee]

Thank you all for your help!!

[estación seca]

The patches on the leaves are worrisome for spider mite damage. Take a tissue, press it gently under the leaf near the stem and and run it to the tip. If there are red or brownish streaks it has spider mites.

[WaterWitchin]

Good call, ES. Or possibly a combo of both sun and mites. The pictures just don't come through with enough clarity other than to guess... at least to my old eyes.