MASDEVALLIA problems. Help!
 

Ok, I did it again. I went and bought Masdevallia. One genera I have never had luck with, but I was determined to try again. Well, now I have (2) Mounted Masdevallia decumana.

On one plant, all of the leaves began having brown spots, black spots, yellowing, pitting, blah blah blah ...
here we go again!

So, can someone help me with what this problem is?
Black spot, Brown spot, black rot, brown rot???

Causes? To Wet? To Cold? Low Humidity? High Temp?

I have them growing on a Windowsill (may be a problem)
with a fan and a humidifier.

Any help is appreciated .....

I've heard that brown/black spotting can be too warm for masdies.

Mine did that when I first had them and kept them in the house. I was advised they were too warm and built a greenhouse to keep them in which I keep as a cool growing area. I've not had the problem since. Humidity is also higher in there, but I think low humidity was the cause of different problems (with new leaves not opening up properly).

Of course it's difficult to say without seeing the spots, but these were brown/black pits, mostly on the underside of the leaves, but could appear on the upper side as well.

As Rosie said, the only time I got spots which sound like yours (pics would help) was when it got warmer than I wanted for the masdies. I only have 2 and the one was worse than the other. I treated them with some brown Listerine as we can't get Physan here and it didn't seem to spread. I am only now able to cut a few of those unsightly leaves off as they age and new ones are appearing healthy and green. I always had fairly high humidity so I don't think lack of it was a problem. It may have been too much combined with warm conditions. I just checked OrchidWiz and decumana is a real cool grower. 67-70F daytime and 48 to 52 at night year round with high humidity of around 80%. Maybe you should try a hybrid with a bit more warmth tolerance and sometimes hybrids just have more vigor and adapt easier to different conditions.

3rd that it can be the warmth issue.

However...

You didn't mention the temperatures you grow yours at...

If you feel temperature isn't the problem, then all I have to say is, disinfect your plants.

If they're coming from out of the country, disinfect them.

Even if they're coming from a US nursery, you may want to consider disinfecting them. Particularly if you think the place wasn't thorough enough with the debugging.

Some Physan 20, potassium permanganate, and Betadine solution does wonders for cleaning your plants. A 20 - 30 min soak in each solution works great!

You may also want to check the roots. Root damage can also lead to bad looking leaves if everything else checks out.

I generally don't like mounting Masdevallias, particularly if you're growing in an area that is somewhat arid. The roots can dry out very quickly.

If you're growing them in a cool house or a modified terrarium, then you can mount them.

I got these 2 Masdevallia mounted because I have no room for any more potted Orchids ----

"Warmth" is not the issue - my temps are quite cool for them, and the Humidity is fine too, so I'm totally baffled as to what the real problem is here with these orchids. Mounted orchids 'dry out' very quickly, but I do have a humidifier within 12-inches of these plants.

I guess my real question is: "What the heck is the real problem with growing Masdevallia anyhow" ? ....
What do they really want ????

Where are you getting them from? If you don't mind me asking.

Masd decumana seems to be able to tolerate quite a range of temperatures as it comes from 1,000 m - 2,500 m in the Andes. You should be able to do fine with these.

I got these Masd. decumana from ANDY'S ORCHIDS.

Well...

Andy's gets his from Ecuagenera. Plants from Ecuagenera need to be treated thoroughly before introduction into the collection.

You might wanna try disinfecting them. They could be relatively recent imports or if they've been with Andy's for a while, they could just have had some die hard spores. Not sure which of the two scenarios it is, but it doesn't hurt to disinfect your plants.

Andy's mounted plants also tend to have quite a lot of moss on the mounts too. You may want to consider taking a look at the roots to see if they're not rotted out.

You don't mention how long you've had the Masd decumanata for, but I think it's important to mention it so I can sort of gauge where some issues may lie.

I'd also like to know how often you water these guys too.

Another thing that might help is a photo. Without a photo, this is the best guess I can really make.

I have Masdevallias that come from similar elevations as the Masdevallia decumana and they're doing superbly well outdoors here in SoCal. They are potted though. Yes, they are also disinfected.

The ones that come from slightly higher elevations are the ones that are really suffering for me right now.

Hey Philip:

I've had these 2 Masd. decumana for exactly 2-days. They arrived on Tuesday from ANDY'S.

One of them was in full bloom when I unpacked it. Gorgeous.

Within 24-hours the leaves started to spot, yellow, pit and obviously become stressed.

It's been the same with every mounted Masdevella I've ever grown - a few years ago I had 4 mounted Masdies arrive from ANDY'S. The same thing happened. I lost all 4 plants. And it was a huge financial loss, as the plants were not cheap.

Problem is I think I need to stay clear of SPECIES and stick with more 'reliable' Masdevallia hybrids that are potted and not mounted !

PATRICK

Masdevallia decumana is among the ´difficult to grow´ Masdevallias in my private experience. Other species like floribunda, barleana, bicolor, tovarensis and many more are easier. And every changing of climate and growing conditions plus the transport is stress for these delicate plants. It doesn´t mean that you can´t grow masdies on your windowsill, but eventually some hardier species will bring you more fun.