What are these black spots on my Cym "milk tea"?

[Phrogz3]

Cabbo , I have been testing "Ed Rosenthal's Zero Tolerance" it is a pesticide and fungicide. I have yet to try it as a fungicide, but I have heard it is great for that use in orchids. I have tried it as a drench diluted at about 40% Z.T. and 60% water to kill white flies and there eggs in the potting media. I have not noticed a bit of damage or slow down in my trial orchids. I am going to be testing it on my leaves this weekend. The best part is it's herbal and safe around pets and children. Oh, and it smells GREAT!
Some of the chemical alternatives are Thiram or Captan. These are commonly used with commercial orchid growers. One advantage that Z.T. has is pests don't become immune to the herbal compounds. So, you can do your pesticide and fungicide at the same time. Less chemical, less cost, less time!

Best of luck,
Phrogz3

[cabbo]

Originally Posted by Phrogz3

Cabbo , I have been testing "Ed Rosenthal's Zero Tolerance" it is a pesticide and fungicide. I have yet to try it as a fungicide, but I have heard it is great for that use in orchids. I have tried it as a drench diluted at about 40% Z.T. and 60% water to kill white flies and there eggs in the potting media. I have not noticed a bit of damage or slow down in my trial orchids. I am going to be testing it on my leaves this weekend. The best part is it's herbal and safe around pets and children. Oh, and it smells GREAT!
Some of the chemical alternatives are Thiram or Captan. These are commonly used with commercial orchid growers. One advantage that Z.T. has is pests don't become immune to the herbal compounds. So, you can do your pesticide and fungicide at the same time. Less chemical, less cost, less time!

Best of luck,
Phrogz3

Thanks alot, I should add the reason I thought it was from sun is that the spots dont rub off with my finger. Wouldn't fungus wipe off?

[Phrogz3]

Strong sunlight is a possibility. It will cause bleaching, and black spots. I did see some yellowing on your plant. The way that you tell apart fungus brown spot from sun damage is the fungus brown spot will have a "watery margin."
Cym. do have bright to very bright light requirements. But, this time of year the sun hangs around a long time in a south east window. your in N.J. I believe. So snow could defiantly increase the light to blindingly bright at some points.Snow is very reflective. Not that I have seen any in forever,but it's been cold enough around my house that it could have snowed in the past few weeks.


Phrogz3