Pleurothallis tripterantha leaves yellowing - Orchid Board

harpspiel · #1 01-02-2021, 10:55 PM

I got this from Andy’s a month ago, at first had it in a brighter spot and also water droplets tended to hang on the tips of leaves. One leaf started rotting from the tip and other leaves started turning yellow, so I cut off the rotting leaf and moved it to a shadier spot and an orientation where water doesn’t hang around on the leaves. That was a week ago and since then more leaves have started turning yellow, but I’ve also noticed a new bud.

I’m pretty sure it’s not too dry, the spot it’s in never dries out. Could be too wet, but I read that it likes to stay moist. Is it just sulking from being mailed and then moved? The yellowing leaves seem to be the largest, so I assume oldest, leaves.

estación seca · #2 01-03-2021, 02:00 AM

I've never grown this one. I don't think it should be so wet water continually drips off the leaves. That could be an old leaf dying, too.

harpspiel · #3 01-03-2021, 02:04 AM

It isn’t in a spot where water sits on the leaves anymore, but it’s not just that leaf, you can sort of see multiple other leaves in the pic that are turning yellow.

Tindomul · #4 01-03-2021, 05:27 PM

I see more than one leaf turning yellow. It's time to check the roots. They probably need(ed) more air circulation. Since you moved it and a bud is forming it may be in a better place. In my experience multiple leaf loss is a sign of root rot.

harpspiel · #5 01-03-2021, 05:38 PM

I’ll check the roots. When I got it the roots were growing through a pad of Sphagnum and hadn’t really attached to the mount, so I removed it from the mount but left the sphag in place. Maybe my conditions are wet enough that I should remove the sphag too - in my conditions some orchids seem to want sphag around their roots and some seem to do better with nothing.

Roberta · #6 01-03-2021, 09:12 PM

I have ended up remounting most of my Andy plants that have sphag between the plant and mount... I understand why he does it, plants are easier to unmount as they grow, and also easier to keep damp in dry exhibit halls at shows. But unless roots are really vigorous, they tend to not attach to the mount. When I remount, the plant goes next to the mount, with sphagnum over the top of the roots for plants that like to stay damp (like Pleurothallids). It may be sulking a bit from the process of being transported. Hopefully, it stops dropping leaves!

harpspiel · #7 01-06-2021, 07:37 PM

Checked the roots and sure enough, most were goners. I think it must have been grown in much drier conditions, and when it transitioned to my Paludarium with frequent misting, the wet sphag pad pressed against the roots did them in. I removed as much sphag as I could from around the roots. Good news, I do see a few green root tips forming, and the rhizome looks good so I think it will recover.

Tindomul · #8 01-06-2021, 09:50 PM

Yea it might recover quickly or slowly. It all depends on how much damage and the health of the plant. However, if you find the right conditions and stop the rot it will recover. How is the ventilation around the plant?

harpspiel · #9 01-06-2021, 10:59 PM

I have a 45 CFM fan in one corner that runs almost 24/7, that Pleurothallis is on the opposite side of the tank next to Bulbophyllum ‘Santa Claus’ and Bulbophyllum barbigerum. I have had some algae and mold issues on that side of the tank, so I’m considering a 2nd fan, but the bulbos both have new growths and are looking pretty good.

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I also have two vent fans that run for short periods a few times a day, to keep the glass dry and encourage some air exchange with the outside. My ambient humidity outside the tank is around 25% so it takes frequent misting to keep the humidity up in the tank, and there tend to be a few moisture “sweet spots” and then other areas that are a little too wet or too dry, no matter how I tweak things.

harpspiel · #10 02-19-2021, 05:40 PM

This has mostly stabilized since I moved it, but it still loses its oldest leaves to slowly spreading brown spots (not sunken though, I don't think it's bacterial brown spot) almost as fast as it grows new ones. I have concluded that it *hates* water on its leaves, more than any other Pleurothallid I grow. Maybe it needs to be even drier.

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Actually I don't know, maybe it is bacterial brown spot. Just cut off the last 3 leaves that had spots, the large brown/yellow one had fallen off on its own. I'm going to spray the plant down with hydrogen peroxide. Does everyone use straight 3% to spray or dilute it? I sprayed with 3% a while ago, then read some more and panicked and rinsed the nearby moss off with RO water, but it actually didn't kill any moss.