Various miniature orchid issues

[shadowteme]

Hi everyone,

I'm having various issues with multiple miniature orchids in my paludarium and I've no idea what to do (or what I've done wrong for that matter...).

It's been set up for a year now and everything went fine initially, most orchids took really well to their new environment growing a million roots, leaves, even flowering. Only one orchid, the Masdevallia Minuta seemed stressed by the move, it dropped all but 3 leaves but then that too seemed to recover, grew a new leaf and some roots, seemed fine until very recently; I've noticed some tiny brown spots on the leaves about a month ago, and today one of the leaves is all yellow.



Then there's the Masdevallia Nidifica 'Alexandra': I divided the original plant and put it in two different places, both thrived from the start, grew lots of new leaves and even flowered. Then in August some leaves changed color overnight; the one closer to the light developed this (beautiful) vivid pink color, the other a yellowy-peach that was different than when a leaf is sick and yellows.



For a while nothing else happened, then they started shriveling, drying, some seemed to have rot, some dropped with no visible cause... but most just dried and have these weird bumps:



They don't move and don't really wipe off so I don't think it's a pest, looks more like fungal issue but I sprayed with a fungicide and it doesn't seem to have had any effect.

Can anyone help with either of these?

[estación seca]

The last two show fungus fruiting bodies. I suspect the fungus is living on dead leaf tissue and not harming the plant.

What changed? Is it more or less humid in there? Has the temperature changed? Maybe the light is too bright? How are you fertilizing your plants?

[shadowteme]

Originally Posted by estación seca

The last two show fungus fruiting bodies. I suspect the fungus is living on dead leaf tissue and not harming the plant.

What changed? Is it more or less humid in there? Has the temperature changed? Maybe the light is too bright? How are you fertilizing your plants?

So I don't have a humidity sensor set up, the one I have is too big to keep in permanently, but when I last checked it was around 70% and it might go up a bit after watering. We did have a hot summer here, the temperature was constantly around 30°C in there but then there was a sudden drop in August (actually that's when I first noticed that color change) like summer was cut in half and since then it's the usual 24°C most of the time, so not all that big a change and there were no swings since then.

Another thing that comes to mind is that I didn't turn on the fan as much because it caused bud blast on a new (in this paludarium) orchid and I had to fiddle with placement and intensity etc. But to be honest my use of this fan was never consistent to begin with, it's not automated and I often forget to turn it on which never seemed to be an issue; the top of the paludarium has a lot of gaps and cut-outs for easy removal so air can move freely.

The light is the same, no change there, every orchid adjusted to it pretty quickly.

I fertilize once a month or so. I'll admit I was not too consistent with that either, not easy to manuver in that tight space. I use a little spray bottle, it goes on the leaves and the moss around the roots as well, never had any issues. I didn't change the fertilizer itself, I don't think the concentration changed either.

One more thing for the m. nidifica; I placed one clump on a piece of driftwood sticking out of the water and the live moss just started to really creep up and around the roots recently. At first I was really happy with that cause it gave a more natural look then I noticed that the wood and sphagnum were kept constantly wet because of it. So that might have been an issue but it doesn't explain the second clump (the one that turned pink) that is in a different place and also sickly.

[tmoney]

mornin! so my attempt at a terrarium was a miserable fail, so please take this worth less than a grain of salt. but, reading your second post hit on what i was thinking and that is the fan and air circulation. the fans made the biggest difference when we had our us and running. and when one fan died ( we had 2 going in there) things started to go downhill. so, for enclosed space growing my experience was that air flow is critical.

that’s where I would start, but im sure other more experienced tank growers will chime in with better advice. also, it doesn’t look like bugs to me either, it seems more climatic. best of luck!

[shadowteme]

Originally Posted by tmoney

mornin! so my attempt at a terrarium was a miserable fail, so please take this worth less than a grain of salt. but, reading your second post hit on what i was thinking and that is the fan and air circulation. the fans made the biggest difference when we had our us and running. and when one fan died ( we had 2 going in there) things started to go downhill. so, for enclosed space growing my experience was that air flow is critical.

that’s where I would start, but im sure other more experienced tank growers will chime in with better advice. also, it doesn’t look like bugs to me either, it seems more climatic. best of luck!

You might be right, but it's just weird to me that for almost a year it's no issue (like I said it was turned on kinda sporadically), and then suddenly this... I also have a smaller vertical paludarium that has been set up for 2 years now, it's way more enclosed with one small, mesh covered gap for airflow, no fan, and it houses three mini orchids all of which are thriving.

Nevertheless, thanks for the advice, I will be more consistent with the fan use

[tmoney]

Originally Posted by shadowteme

You might be right, but it's just weird to me that for almost a year it's no issue (like I said it was turned on kinda sporadically), and then suddenly this... I also have a smaller vertical paludarium that has been set up for 2 years now, it's way more enclosed with one small, mesh covered gap for airflow, no fan, and it houses three mini orchids all of which are thriving.

Nevertheless, thanks for the advice, I will be more consistent with the fan use

well, i wish you best of luck! but again, don't listen to a word i type. you could very well have some serious mold action happenin, i have no idea in which case, drag it all out and clean? excuse to buy some new plants?? i just gave up when it went south, hahaha!

[shadowteme]

Originally Posted by tmoney

well, i wish you best of luck! but again, don't listen to a word i type. you could very well have some serious mold action happenin, i have no idea in which case, drag it all out and clean? excuse to buy some new plants?? i just gave up when it went south, hahaha!

Well, dragging it all out and cleaning is not really an option unfortunately, that's like the biggest con of trying to make the plants grow on wood and stuff so it looks as natural as possible; something goes wrong too bad... can't remove

But def a great excuse to buy new plants

[estación seca]

Lack of air circulation is a big problem for terrariums. I would suggest improving that.

Plants don't grow without fertilizer of some kind. Once a month during the growing season isn't enough. The plant might have been coasting for a while on nutrients remaining from the previous grower. I would definitely increase the fertilizer.

You don't mention what kind of water you are using. Most of these cloud forest orchids need very pure water, like distilled, rain or reverse osmosis. If you're using pure water you very much need to fertilize, as well as use a calcium and magnesium supplementation, since these elements aren't usually in regular fertilizers in adequate amounts due to solubility issues.