I know there are other threads regarding the yellowing of leaves, but frankly, I'm too lazy to go hunt them up, but I'm starting to get really concerned. A few days ago, I mentioned that my Zygo had a yellow leaf, and I was advised not to worry, but that it would come off. Well, today it did that, and that was fine, because I expected it, and the rest of the plant looks just fine. Well, today I also noticed that I have others that now have yellow leaves on them, including the one that had a spike showing thru the sheath in a backlight condition.

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Is it possible that it's just too warm for them out there? It does get pretty warm and humid at night, and although I have a fan going, it's not very strong. Should I turn on the a/c out there at night? Or (perish the thought), is there something more serious afoot here. I don't exactly like the way this one looks, with that big black area, but these plants had been outdoors originally, and had signs of sunburn, so I wasn't too concerned at the time. Should I be worried now?

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Except for this awful heat we've been having (which of course is normal for here), everything is basically the same. I mist daily, and water as needed.