Red leaves: Just a mineral deficiency or something more sinister??

[Monks-in-Miami]

Over the past few weeks I've noticed that the leaves on a couple of my orchids, specifically an epidendrum and a dendrobium, have started to get these reddish areas. Also, a new shoot on the dendrobium is also coming out with these red leaves. Could this be just that they are deficient in something (calcium and/or magnesium) or should I be worried about something worse? The two plants are not together, nor do they seem to be in any distress -- the leaves are firm and the plants are otherwise (in my opinion anyway) healthy. I've read that cold weather can cause reddening, but here in Miami, our coldest day so far has been about 75!! LOL

[78Terp]

I don't know if this is the case that you are seeing but some orchids do this.

Many of the orchids I am aware that do this is a response to the amount of light exposure it is getting. For instance, Tolumnia are healthy when green but likely won't bloom because not enough light. As the fans turn red, then the flowering cycle is more likely.

[sciencegal]

Magnesium deficiency will cause reddening of leaves. I looked up magnesium deficiency in orchids and many of the photos look like your situation.

[JDT]

I agree with Karin. This time of year I spray all of my orchids with Potassium and Epson Salts once a month during the summer I will spray them twice a month. One of the orchid vendors in Homestead has this remedy in his book on orchid growing in Florida for taking care of this problem.

I would make a suggestion but we are not suppose to use vendor names in postings, you can sign up for receiving Private Messages in you settings, that way we can.

[Monks-in-Miami]

I figured it might be mineral deficiency.

Thanks Jack, I've turned the Private Messages on.