Black layer on Cattleya growth, spots

[NewBloom]

Hello Geeks,

I bought my first catt in February and repotted in late March when the flower dropped. The plant was kind of top heavy as it was in a 3 inch pot.

It came with the markings on the leaves you see in the last photo.
I moved it up to a 4.75" dual core pot from Repotme and moved it outside in an area beneath a shade cloth. Time went by, new growth appeared and I thought things were going great.

Then about a month ago, a friend who's got an orchid collection warned me that my plants may not be getting enough air circulation where I had them. (I have limited orchid friendly areas at my house). I kept a closer eye on my collection and one day noticed something was off and thought the bark mix wasn't working out. I took her out of the pot and found mushy roots and the dark growth near the larger new bulb. I cut off the dead roots and down potted.

It's been in the new pot for about 3 weeks, I think. It's in a drier type mix of coconut chips and LECA. I treated it with KLN rooting concentrate upon repotting and have moved it. I'm watering once a week and being extra careful to let the mix dry out. The humidity is high here now (80-90%). I'm wondering if there's anything I should be doing. The new growth seems to be progressing but I'm not out of the woods.

Btw, I had a hard time repotting because of the plant's L-shape. Even with the rhizome clip, I couldn't get it into a stable position and it would wobble if I touched it. Today, I tinkered around and found a way to anchor her into the pot without hurting the new growths. That pic isn't included.

The black part (BirdsEyeSpot2 pic) when I touch it, it can be peeled away. It's like a leaf layer. Should I peel it off? I left it alone, figuring the plant knows way better than I on what to do.

You can see in Catspot2 that the black area has now spread to the part where the new growth and old can connect.

Catspot features another new growth that has the same problem. In Catspots you can see a small dark area starting on the older cane.

Any advice on what I should do to help her recover is appreciated.

[kmarch]

The black in CatSpot2 pic are bracts that have died off and turned black. Bracts are protective leaf-like structures that protect the new growth as it is growing. They usually stay green for longer than this. I'm not quite sure why yours hae turned black. Are they soft ro mushy? If yes, remove them immediately. If not I'd be inclined to leave them for a while longer. After the growth is mature and all of the bracts dead and dried up, you can remove them.

In the last pic, the leaf looks like it has been stratched or perhaps nibbled?

Your cattleya looks a little bit dehydrated. How often do you water it?

[digitalgate]

the last picture look like leaf miner of some sort.

[NewBloom]

Kmarch, the bracts/black layer feels similar to the rest of the new growth. I wouldn't say it's soft and mushy but it's not dense. This being my first catt, I'm not sure how a bract is supposed to feel to the touch.

If I wanted to remove the bract I'd probably need a tweezer to pluck it off. Do you think the fact that the part where the new growth and old cane meet has gone black also, is a red flag?

I agree she looks dehydrated. One of the canes is very pleated and was like that upon repotting. Before, I'd water 1-2 times per week and I'd always check the bark. I'm doing it about once a week now since she's been repotted. Lots of roots were cut off, so my thinking is to not aggressively water while the plant's in recovery. Not sure if that's the right thing or not. This new mix is less moisture retentive (the bark was soggy) and with the plant being a bit unstable, I don't poke around to test the moisture below the surface.

What's your advice on watering? I've read up some culture sheets and even the grower said to let it dry out a bit before I water but I've been careful not to underwater. At least that's what I thought. The plant did come with some pleating already. Would a pleated bulb regain plumpness once it's watered correctly?


Digitalgate, the leaves had the markings when I bought it from the grower. A friend suggested it might be sunburn. It's never gotten worse but I was curious.
If I knew in February what I know now, I probably would've passed up on this plant. But the flower and fragrance seduced me.

[digitalgate]

hmmm, just a little dehydrated other than that should be fine

[zaeem]

THE BRACT,turning black should be watched if it progress further then a surgery.but leave it it may stay and not interfer with the leaf growth.But catts need sun and water not soggy.
zaeem

[NewBloom]

I'll keep an eye on the darkened bracts.

Should I keep the plant in shaded area since it's been repotted only 2-3 weeks ago with root loss? Or is it okay to let her have the regular amount of light that catts like?

Thanks again for all your feedback.

[Brooke]

I would pour some peroxide over the bract to hopefully keep any bacteria from exploding and possibly losing the pbulb.

It needs to dry out so put it in it's regular grow spot. It is water trapped in the bract that created the problem.

Your old pbulbs will plump up if you have viable roots. If they are devoid of roots, no they won't plump back up. Don't worry about it, old rootless pbulbs live a long time and still give energy to the plant.

If you always grow outside, you might consider switching from bark to a clay pellet mix, i.e. Prime Agra, Hydroton. Heavy rain is not an issue and the media will never break down. Many of the Geeks in Florida have switched to the inert ingredient and are happy with it. I use it for catts in the g/h.

Brooke

[NewBloom]

Brooke, you might be onto something. I think there were a few times where water sloshed over the new bulbs. I've been more careful about it and now that you bring it up, I'll be extra vigilant with how I water.

The new potting medium is a mix of coconut chips, Hydroton, charcoal etc. I drains better than bark and doesn't hold too much moisture.

How often should I treat the bracts with peroxide? Will the spots on the old cane remain dark even if the problem's contained? I ask so I'll know what the signs of improvement would be.

[Brooke]

Once anything turns black, it will stay black. As long as there is no active infection growing, it will be fine. Improvement is having the area not grow.

Every time it rains Mother Nature sloshes water over the new growths - you happened to have a small bacteria try to set up house keeping.

Picture #7 looks like a slug had a snack.

Brooke