Question
QUESTION: Hi Jim,
I have a phaleanopsis since 2005 and I noticed about 6months ago a little black spot on the stem towards the bottom of the plant. I just noticed that there is now a white little line going thru the black spot. Is this a fungus? In researching this on the internet I am more confued then anything. Thank you for your help.

ANSWER: Hi Connie,

My first question is: Has the phalaenopsis plant been growing okay in the 2 years you've had it?  

My second question is: Has the black spot remained the same size or gotten larger?  

Question 1) If it has been growing and making new leaves every 6 months or so, it probably is nothing to worry about.  Also, have the new leaves matured to the same or larger size than the older leafs?  A healthily growing phalaenopsis will grow the newer leaf to be as large or larger than the older leaf.  

Question 2) If the spot size has not changed, it may not be anything to worry about.  It may have been caused by a little handling damage and as it healed it turned black.  But, if it has grown in size, that could be an indication of possible fungus or bacteria infection.  If it is one of these and it has been growing for 2 years, the health of the phal would have declined to the point where it would be barely alive by now or even dead.  

Hope this helped.  

Jim Kawasaki
San Jose, Ca.


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

QUESTION: Hi Jim,
The plants new growth since I have had it has only 2 new leaves (4 total). They are not as big as the old leaves maybe 1/2 the size. I do have alot of new roots shooting out. I think this is because I am new to orchids and potted it in a big pot and did not water correctly in the beginning of owning this plant.

The black spot (looks alittle like decay) has gotten a little larger and is changing color. If it is fungus/bacteria, what would be the best treatment?
Thank you,
Connie
Antioch, CA

















ANSWER: Hi Connie,

If the new leaves did not grow to be as large as the older leafs, that usually indicates that there probably is some rotten roots within the pot.  Repotting into too large a pot can compound the problem because the potting media remains wet much longer.  For most orchids, it is best to use the smallest size pot that will hold the roots.  Roots growing outside the pot should be lightly misted in the morning to help maintain moisture in them.  

If the black spot is slowly growing larger, you can try treating it with a good plant fungicide/bactericide.  It will take several applications over weeks to control it and hopefully kill it before it kills your phal.  If surface treatment does not control it, you may have to perform a little surgery to remove the spot then treat the open wound with the fungicide.  Hope it doesn't come to that.  

I've never been to Antioch, been close though.  I go to Calistoga 3 to 5 times a year, taking 680 to Benecia then 780 to Vallejo, etc.  

Jim Kawasaki
San Jose, Ca.
 


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

QUESTION: Hi Jim,
Thank you for all your help. I have ordered Physan 20 to use as a fungicide/bactericide. Hopefully that is good stuff, since the nursery I go to did not know what to recommend. I will also repot in a smaller pot when I get the product in. (next week). Hopefully that will help the problem. (I do not know if I am up for the surgery part yet. )

I have an uncle that lives in San Jose. We just moved up north last March from Southern California. So far we Love this area.

I will keep you updated on the Phal. and Thank you again.

Connie

Answer
Hi Connie,

Physan 20 is a pretty good one to use, just be sure to use it according to the instructions.  

Plant surgery is not that difficult, you just have to be careful to not injure yourself while performing the operation.  In most cases, the plant survives the surgery without complications.  

Don't believe I've ever met a Pierson here in San Jose, of course there are a lot of people in San Jose I haven't met.  (grin)  You must be thankful you moved when you did as you missed all the wild fires down south.  

Jim Kawasaki
San Jose, Ca.