Masdevallia potting experiment

[Erythrone]

The issue that I see most critical for the pleurothalid group in general, that I've not seen discussed (except by Goods) is humidity level. The bulk of them requiring very high humidity at all times. (70-80% minimum)

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I agree. They are tricky about relative humidity.

 

[Erythrone]

So what do masdevallias need for light and fertilizer? I've heard so much contradicting info on the two subjects. Ranging from Catt light to Phal light and heavy feeders to light feeders.

IMO many Masds can take higher light levels if the temperature is cool but not as much as the larger sun loving species Cattleyas. But I must say many of my Cattleyas are compact hybrids that grow well under the same light level as my Masdies in winter.

Here is an very interesting paper about Masd coccinea, written by Theresa Hill.

http://hillsviewgardens.com/textfiles/Growing Masdevallia coccinea.pdf

 

[Paul Mc]

Thank you all! This is exactly the type of discussion I was hoping for. I'll read that paper in a bit!

 

[Rick]

"There is an average of rainfall that fluctuates between one thousand five hundred and two thousand eight hundred cubic meter, this is the reason why the monthly relative humidity is in direct relation with the rains, by which the average humidity is 77% during the dry months and 91% in the rainy months."

I pulled this off of a site on Machu Picchu. Now there are highland and lowland Masdies, and Masdies found in other parts of SA, but one of our favorite Masdei species (veitchiana) can be found growing on the walls of Machu Picchu.

Fairly open/bright, but even at the warmest, it looks like it maxes out at 80F, with lows in the low 50's.

There are websites that you can get the moment by moment temp and humidity at Machu Picchu, and I saw some noontime values that dipped into the 50-60% range, but past noon, it rises pretty quick again to >70%.

 

[Rick]

http://courses.missouristate.edu/alexanderwait/notes/lecture notes/lecture 11.htm

Check this out Paul I think implications of low humidity, high temp, and excess fertilizer are integral with issues concerning water and nutrient transport in orchids (especially in upland Pleurothalid species)

 

[Paul Mc]

The Theresa Hill article was very interesting. Some good information there.

 

[Paul Mc]

Rick, that's a good breakdown of how plants deliver nutrients. I think it's aster of finding the correct balance for these guys.

In a side note, I turned the fan off while I was out of town for two days. I returned and maybe half the water had been used as opposed to having to fill daily. I upped the size of The water reservoir to compensate. However, they are still much cooler to the touch than my test potted plant next to it.

 

[Erythrone]

For a cooling effect, you can just put the pot on a larger clay pot and fill with moss. It was great for my Masdies last year.

 

[The Orchid Boy]

I just transferred my only masdevallia into s/h in clay exactly 15 hours ago. It isn't close to a fan or anything, is under T8 lights and hasn't used near as much water as I thought.

What about temperature needs for masdevallias? What is the most comfortable high and low temps that the average cool growing masdevallia can thrive in? What about root temps?

 

[Rick]

I just transferred my only masdevallia into s/h in clay exactly 15 hours ago. It isn't close to a fan or anything, is under T8 lights and hasn't used near as much water as I thought.

What about temperature needs for masdevallias? What is the most comfortable high and low temps that the average cool growing masdevallia can thrive in? What about root temps?

I think humidity is more important than temperature (but the two work together).

There's lots of species of masde, and tons of hybrids. So really can't generallize for all of them. But try not to let your top end temp go above 80, and try to get into the 50's at night.

But if you can't maintain a humidity of 60% at that low end temp, you'l probably still be in trouble.

 

[goods]

In regards to necessary humidity to grow Pleurothallids versus low enough humidity to generate an adequate cooling through evaporative cooling, I think growing these in terrariums (high humidity) and hooking up an outside cooling system using home air instead of terrarium air (lower humidity) for cooling is the best combination. If the ambient humidity in your house is less than 50%, you can simply take a rubbermaid container, cut a square out of the side (where you'll attach a cooling pad), add in an aquarium pump that passes water over the pad and a fan that pulls outside air into the container. Connect this to the tank using a dryer duct or something similar and attach a fan to one side of the duct to pull air from the rubbermaid and push air into the tank.

The key to this is to keep the ambient humidity in the room where this is growing as low as possible. The lower it is, the more efficient the cooling will be. If you live in an environment where the ambient humidity is naturally high for much of the year, this won't work. I've tried it in Louisiana and aside from large greenhouse cooling pads, there is no cooling here.