Question
Hello Jim,

I bought an orchid in September and it had been perfectly fine until two weeks ago.  First, I came back from a 5 day vacation and one of the 5 main leaves had turned completely yellow, the other 4 leaves were fine.  Then, one by one, each of the 8 blooms fell off.  The main stem off of which the blooms grow has also turned yellow at the top two inches.  The orchid is planted in a moss mixture and there has been no new growth.  I water it once a week, but when I got back from my vacation it still felt wet even though I hadn't watered it in a week.  Do you know what might be going on with it and what I can do to fix the problem?  Thank you so much; I really appreciate your help!

Best,
Nina  

Answer
Hello Nina,

You did not say what kind of orchid you have but if the leaves are sort of oval in shape and are thick and fleshy, it probably is a phalaenopsis orchid.  I will answer you assuming that it is a phal. but if the description is not correct, write back with a description of what yours looks like and I'll try to help with it.  

As you noted after returning from vacation, the moss potting media was still rather wet which is a problem with moss, while the exposed moss may look dry after a week, inside the pot it probably is still pretty wet.  Moss is great for persons who do not water very often but terrible for people who water more frequently.  

The problems you noted with the blooms falling off and a leaf yellowing are symptoms that there may be a problem with the roots within the moss.  Orchid roots need both water and air to survive but when kept constantly wet they soon become rotten because they are not getting some air around them.  This is similar to being held under water and without air they soon drown and die.  

The stem turning yellow from the tip downward indicates that it is slowly dying but don't worry as this is fairly normal.  Cut the stem off as low as you can, leaving about an inch or two at the bottom.  

My suggestion would be to repot it into an orchid mix that is more open, such as one that contains bark.  After repotting, place it in a warm shady place for 2 to 3 weeks then move it to you have had it growing.  

Before watering it, check to make sure the potting media is barely moist.  I like to lift the pot to see how heavy or light it feels, if it still feels a little heavy I will wait another day or two until it feels light before watering.  Along with water, feed it a balance type orchid fertilizer to keep it growing and healthy.  

Phalaenopsis usually produce blooms in late winter through spring, so be on the lookout for a new stem to begin growing from between the leafs.  

Hope this helped.  

Jim Kawasaki
San Jose, Ca.