Help leaves blackening!!!!

[Ross]

Sorry to see this so late, but I doubt this is a fungus or any other disease. I suspect sun damage. Since you are in Florida and this is summer, the sun intensity is really high. This looks like classic sunburn of orchid leaves to me. It will continue as long as the plants are in the full sun. You need to move them to a shadier location (keep in mind the full sun in Michigan is not the same as full sun in Florida) (and shade in Florida is not the same as shade in Michigan) and hope for the best. The black indicates completely burned foliage which will never change back to green. Now I could be wrong, but in this case (I've seen it first-hand) I doubt it. I am confused that only the Cats appear with this symptom, however. Could they be in slightly different light?

[saltydog7seas]

I am now actually quite sure it is a fungus, like I said, I cut all black off yesterday evening and put them in complete shade last night. Today they had new completely blackened leaves. Also the leaves aren't dried out, they are rubbery. And there are about 20 cats that have been in the same location for about 2 years. We have just had rain almost everyday for about 2 weeks now. In one day we got 3 inches so it's not the typical afternoon quick shower. Alot of the roots are above the medium and still look healthy so at least that's a good sign. I will try the stuff from sam's tomorrow. Do you think there is any chance that if it is a fungus that those pseudobubs will survive after treatment?

[BikerDoc5968]

Don't throw in the towel until the fat lady sings

[ghosoff]

Hey how is everything going man yeah I have seen the same problem exactly how u explained it I have about 50 something orchids in a green house and some of them got one strange problem and the Cattleya's have exactly what u have showed and explained but I ave no clue what I should do !!! I will try yo take some pictures today!! But I think I am in the need help zone too but at 1st I thought sun burn then I got that taken care of but now I think it is clearing up a little but what i think the problem is because I check my waters PH yesterda and it was 8.0 so in your area that might be the culprit!! So I started using my PH down and some other stuff now and I will see what happens !! I will put some pictures up later!!

[saltydog7seas]

The only variable that I know of that has changed for mine in the last 2 years is the amount af rain we have received. I'm going to try the ProForce today.

[Djarum Black]

I don't know if it will help, but I found this info on orchid black rot when looking up the problems with your plants. It sure sounds very similar to what you are talking about.
It mentioned cattleya's being the number 1 target as well as plants being left too wet.

Here is a link Dendrobium Buvee Orchids, Dendrobium Buvee orchid, Dendrobium Hybrid orchids, Dendrobium Orchid Growers

Look under orchid black rot

I have my fingers crossed for you and your plants! I know there must be hope! Don't give up!

[Swamper]

Thanks DJ. Great link and info. Ive still got my fingers crossed for you Saltydog

[saltydog7seas]

I sent her to Sam's to pick up the ProForce, but she got the oven cleaner as opposed to the disinfectant. So she's going back today to exchange it and I'll have to do it after work. That does sound like what this is. I just can't believe how quick it spreads. I have one little guy that only has two psuedobulbs and it has already spread into them so I have a feeling he's not going to make it. If the disinfectant does work the rest might live but they will have to be cut way back. Thanks for all of the suggestions so far.

[Swamper]

I stopped off at a friends house on the way home from work. He showed me his catt that he moved cause it got 'sunburned' and there it was a black leaf. Soft to the touch. I asked him how he figured it was sunburned when it was in such a shaded area under a tree. I couldn't help but think of yours. I will be keeping an eye out to see if it spreads or heals. He would be devestated if it spread a lot. That catt is huge and beautiful.

[saltydog7seas]

Absolutely, that was my mistake. I thought sunburn at first, put them in the shade and didn't give it much thought until about 3 days later and by then it had just exploded.