Question
The leaf on my orchid has a spot that is dark and soggy looking.  It gets bigger by the day.  What should I do?

Answer
Hello Kristi,

From your description of the problem, it sounds like it may have a bacterial infection.  Using a sterile cutter, cut off the entire leaf then look at the cut.  If there are some dark spots evident, that could mean the infection has progressed into the plant and you may eventually lose the entire dendrobium plant.  You can try saving it by cutting off the infected growth with a sterile cutter (do not reuse the first cutter since it has been contaminated).  Look at the cut to verify there are no dark spots visible, hopefully there will be none but if there is even one tiny spot visible, that could mean it has progressed to the next growth and that one should be removed also.  

It is VERY important that you use a sterile cutting instrument to make each cut or you take the chance of spreading the infection each time you use it.  Here is what I suggest you do, listed by order of effectiveness in working with problem orchids.  For removing a leaf, I use industrial grade single-edged razor blades that can be found in paint and hardware stores, discard the blade after making a cut - do not reuse them.  For larger cuts I use garden shears that I sterilize using a small blow torch to flame sterilize.  If you don't have one you can try sterilizing your cutter by soaking it for 10 minutes (between each cut) in a super-saturated solution of TSP.  The last choice would be soaking it in isopropyl alcohol for 10 minutes.  

I hope this helps save your dendrobium orchid plant.  

Jim Kawasaki
San Jose, Ca.