Masdevallia 'Angel Frost' Problems - Page 2 - Orchid Board

stonedragonfarms · #11 07-22-2012, 09:17 PM

To me this looks like too much water and too high of heat; once the day temps go much over 85F on these, without constant air movement, shade and mist, you sort of just "cook" the roots. First the tips of the roots die, then the plant will start to shed its mature leaves (those at the center of the plant usually); next the leaves a bit further out will go and finally the new leads will succumb. Any newly developing leads will start to grow, but will just sort of stall out, especially if the conditions have been persisting. I'd say a good rule of thumb for the bulk of the masdevallia hybrids is to grow them somewhere in the 75-78F range as a daytime high (though shading, misting, heavy air circulation, etc. can aid with higher temps), with a 10-20F drop at night. They need a constant flow of fresh air around and over the leaves, pure water with low TDS and high humidity for optimal results.
Just my 2c,
Adam

AnonYMouse · #12 07-22-2012, 11:35 PM

Quote:

Originally Posted by stonedragonfarms

To me this looks like too much water and too high of heat; once the day temps go much over 85F on these, without constant air movement, shade and mist, you sort of just "cook" the roots. First the tips of the roots die, then the plant will start to shed its mature leaves (those at the center of the plant usually); next the leaves a bit further out will go and finally the new leads will succumb. Any newly developing leads will start to grow, but will just sort of stall out, especially if the conditions have been persisting. I'd say a good rule of thumb for the bulk of the masdevallia hybrids is to grow them somewhere in the 75-78F range as a daytime high (though shading, misting, heavy air circulation, etc. can aid with higher temps), with a 10-20F drop at night. They need a constant flow of fresh air around and over the leaves, pure water with low TDS and high humidity for optimal results.
Just my 2c,
Adam

Been there, done that.

What I learned about growing masdies in intemperate climates (for them, anyways) is to avoid saturating the medium (sphag) just prior to and during hot spells. Keep them just shy of dry for the duration (your milage may vary). Hot spells for me usually only last a couple of days but can be as long as a week. Regular misting with good air circulation will provide an evaporative cooling effect. A humidity tray with gravel (I use lava rocks) will add more surface area for the effect. Ceramic and net pots work better for me than regular plastic pots.

Another factor may be the type of plant. I've found that compact growers succumb to this more easily.

My advice is to check the sphag. It will develop a faint but distinct smell not normally present and may grow a slight gray cast.

I recently flushed the media without checking the weather forecast.

I moved the affected plants to where they get a strong fan breeze and crossed my fingers.

isurus79 · #13 07-24-2012, 11:37 PM

What type of water do you use? I doubt this lead to your rapid leaf drop, but using tap water is usually not recommended. Any recovery might be hampered by poor water. Just a thought.