Question
QUESTION: Hi again, Jim.  I have two phals that have each lost a leaf -- on each, the leaf became shriveled and yellow.  I have been repotting my phals into new media (from the sp moss they came potted in), but these two have flower spikes, so I have been hoping to repot after the flowers are over.  The mix seemed wet to me, so I watered less over the last few weeks.  My question is this:  How can I tell if the leaves that have died are the result of too much water causing the rotting of roots or of the mix being too dry?  If you think repotting now is critical to the plants' survival, I will do so.  Thanks in advance!

ANSWER: Hi again Susanne!  

It all depends upon which leaf has fallen off.  If it is the bottom leafs, there probably is nothing to worry about but if it is one of the upper leafs, try checking the base of the leafs to see if there is a black sooty stuff there.  If there is, it might be a fungus that caused the leafs to fall off prematurely.  Fungus can grow quickly when there is water left on the leaf overnight, that is why I usually recommend watering in the morning to allow enough time for the water to evaporate by night.  Also, having some light air movement helps the evaporation.  

If it wasn't caused by a fungus infection, it might be due to root rot.  Try smelling the potting media to see if there is a sour odor present.  If there is, that would indicate the media has gone bad and should be replaced.  You can repot now or wait a while until most of the blooms have died off, the decision is yours.  (grin)  

Hope this helped.  

Jim Kawasaki
San Jose, Ca.


---------- FOLLOW-UP ----------

QUESTION: Jim, the leaves were the bottom ones.  Does that mean that the bottom leaves fall off on healthy plants as they age and grow new ones at the top?  I am a hopeless newbie!  Would you please repeat your recommended potting mix (was it perlite with the bark?)and a recommended feeding routine?  Thanks again -- if my phals live it will be because of your help!

Answer
Hi again Susanne!

Yes, the oldest leaf is the bottom one and will naturally die and fall off over time.  What is not necessarily natural is the bottom leaf to fall off each time a new leaf emerges from the top or crown.  It is not unusual to have six or more leaves on a healthily growing phalaenopsis.  Also, any new leaf should grow to be as large or larger than the previous leaf, if it ends up being smaller, that could indicate a problem that needs your attention.  Problems such as broken down potting media causing root rot or too much or too little fertilizer or water.  

You can use straight orchid bark or mix 10% to 15% large size perlite.  I would stay away from mixing peat moss, vemiculite, sphagnum moss or similar materials unless you are a habitual underwaterer.  

There are many theories about feeding routines but I prefer feeding at each watering because I don't have to think "is it time to feed or not?".  Other persons might feed every other watering, once a month, etc.  Also, there are some time release fertilizers that work well and are easy to use, just throw some on top and it automatically feeds each time you water.  

NO!!!  If your phals live it will be because of you and your efforts!  

Hey!  I was a hopeless newbie like you about 40 years ago!  Back then there was no internet and easy access to orchid growers, it was trial and error (many many errors!) until I bought some orchid books and joining a few orchid clubs.  In many respects I still feel like a newbie because there are so many different kinds of orchids and when I buy a new type I have not grown before, I am just like you, looking for answers on what to do and how to grow it.  In closing, I do not consider myself an orchid expert because experts already know everything and I am still learning.  

Jim Kawasaki
San Jose, Ca.