Bumps on orchid leaves spreading
 

Hello, I'm fairly new to growing orchids, and need help figuring out what's wrong! A few days ago I noticed my orchid had tiny raised bumps on some of the leaves. I couldn't figure out what they were, so I left them alone. Today when I went to water my plant I noticed they seem a tad big bigger, with scabs in the middle! Will they hurt my plant?

I suspect physical damage but, let's get experts opinions...

Are you splashing cold water on them, by any chance?

Hello, and thank you for replying! The only thing I can think of, is when I cleaned the leaves off with a damp paper towel, but dried them afterwards. Otherwise I really try to keep water off. I've noticed today it looks like the bumps are spreading to new leaves..

Probably edema http://staugorchidsociety.org/PDF/Ed...ySueBottom.pdf

That definitely seems to be it! I only just recently got it, and I have just been watering it when the sphag it's in gets completely dry and crunchy. It takes about a week for it to get dry, is it ok to be watered that often? I have it in 75 degree temps, sitting in a west facing window with indirect sun.

Thanks for putting the edema pdf link. I couldn't find anything here in search using 'water warts'.
I had to learn about this the hard way living in the rainy and gray PNW! I think this pdf should be front and center in any sticky care tips for beginners (if it's not already somewhere on here!).
I had queried my local orchid society with photos of bumps on some Phals and no one responded. Won't be joining them! It took quite a bit of searching photos online until I discovered what was going on.
'Water warts' are a very real thing and I want to find an exact scientific explanation of how orchids 'work' besides 'the roots absorb more water than the leaves can transpire'. Maybe someone here has to the full rundown on how Phal's (or all orchids) systems work?
Today is my normal watering day, but since it snowed this morning and has now turned to gray rainy skies = no watering will be done today. I've learned to wait - days if needed - until blue skies and sun come out and THEN take everyone to their bath tub soak, in the mornings only, noon the latest. Any orchid lover living in the rainy PNW needs this info, it will save them a lot of worry.