Phal with dark green /red leaves

[Dorsetman]

Root photosynthesis is a popular fallacy, but a scientific imposibility. Photosynthesis requires free flow of gases into and out of the cells, so as let in the needed carbon dioxide, and that diffusion requires effectively open holes. Roots don't have that kind of structure. Sure they have passages through which water can enter the cells, but they are not ooen ports. The water passes through a semi-permeable membrane,due to osmotic pressure.
But why would a plant even need to photosynthesis in its rootts ? It has specialist structures for that purpose, called leaves.

[Carolla]

I was curious about that statement, Geoff, so I looked online. According to Michigan State University ( http://www.hrt.msu.edu/faculty/Runkl...sis_Part_2.pdf ) the following is the case:

"Phalaenopsis roots that are ex-posed to light have chloroplasts and perform photosynthesis. A majority of phalaenopsis growers in Taiwan and the Netherlands, and increasingly growers in the United States, use clear pots that allow light to penetrate the pots. Root photosynthesis likely contributes little to total plant photosynthesis. However, because phalaenopsis roots avoid darkness, roots of plants grown in clear pots generally stay inside the pot better than the roots of plants grown in opaque pots."

Perhaps orchids, being epiphytes, have abnormal roots? I'm not the expert, I have heard from many I consider experts that Phals can photosynthesize in their roots. I consider you an expert too though.

[SusanLee]

Photo synthesizing makes sense to me. And the orchids I have respond well to having their roots exposed. Aren't phals epiphytes? I have started treating them like that and they seem to like it. I just got a new nook with a camera so want to get a pic of the phal that started this thread...

[SusanLee]

Once I found out that phals are epiphytes I began treating them much differehtly, with attention paid to their roots, especially those in the air. They seem to be doing well and I have let those air roots be and they seem to love the light. In time I'm sure they'll let me know if they like the light and photosynthesis abilities it presents

[eorchids]

the upper side of the leaf is dark green, the underside is dark purple-red, uniformly across the entire length of each leaf. New leaves have this same coloration.

Some Phal. species, maybe in the parentage / ancestry of your Phal., have leaves like that, particularly Phal. sanderiana.
1 Upper side 2 Under side

[SusanLee]

They are that color, yes. I have two, one has wrinkled leaves like the one pictured, leaves are smooth on other. What does "ascendancy" mean? Great thread going on here . Thanks and Happy New Year to everyone!

[Carolla]

Wrinkled leaves means that the plant is not getting enough water. It could be not watered often enough, or that the roots have suffered damage from too much water, broken down media or the wrong media. When the plant gets enough water later, the badly wrinkled leaves do not plump up, but it will grow new ones that are happy (over time) and lose the older sad ones.

Here are two pictures of the same plant, one when a friend gave it to me after his wife underwatered it and one a couple of years later with new leaves.

[eorchids]

I'm sorry. I used a wrong word, I suppose.
"maybe in the parentage / ancestry of your Phal.", is better I hope.

[SusanLee]

Very nice rescue job! I recently brought one home that had been forgotten in a corner and had droopy dessicated leaves. It's leaves have regained their stiffness and it is growing a new leaf

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I figured that's what you meant. It's nice time have a sub species name, thanks