Should I worry about the black in new growth
 

I have pics of 2 plants that the new growth is black. This has been going on all summer off and on.
Does anyone have an idea??? What should I do?? The rest of the plant looks ok.. They have been out side and its been really hot upper 90 for weeks.
Thank you for your help.

Ca and/or Mg supplement?

Someone will be by to explain further.

Sorry, gotta go.

I agree, Calcium deficiency. Add oyster shell, milk (use milk only if orchids are outside) or some other type of Calcium. Powdered Milk or Cal-mag is probably the easiest absorbed. These growths may not survive but the next ones will.

Maybe calcium, or maybe just water left collected in the crown of those growths that fostered an infection. The growths progressed quite a way before the issue - far more than I would expect of a calcium deficiency.

What is your water supply and what are the details of your feeding regimen?

Or maybe there's calcium but your plant is not getting what it needs. To solve this issue, keep the media pH level between 5.2 to 6.5.

I bet you're not watering enough.

While I agree that one might want the media pH in that range, how does one control that?