Question
My kids got me this beautiful Orchid for my birthday last year. I have had it for 13 months now. I transplanted it, removing all the dead roots about 3 months ago. It rewarded me by sending 2 new shoots and it grew in height. We had our first cold spell last week and my orchid has been declining since then. I have it on the window in my kitchen. Two of the older shoots have hollowed out and fallen over. The leaves are turning & falling off. One of my new shoots has lost all it's leaves.  I'm afraid it's dying. How do I save it?

Answer
Hello Tina,

What nice kids you have!  

I am not certain what is causing the problem with your dendrobium orchid but here are some things for you to look at and consider as possible causes.

What was the reason you transplanted it?  Was it becoming overgrown in the pot?  Was the health declining?  Were the dead roots soft and mushy when squeezed?  The reason I ask these questions is because dendrobiums are one of the orchids that do not like to be repotted very often plus they really do not like their roots disturbed very much.  If possible, leave it alone until the growths (canes) are beginning to grow over the pot rim.  Also, it is better to leave the rootball intact unless there are many soft mushy rotten roots present.  

How close to the kitchen window is it?  Although the kitchen may feel warm, it can be 10 or more degrees colder right next to the window unless you have multiple pane windows.  Also, if the window had been opened during a cold spell, the sudden change in temperature could cause it to go into shock.  

On the shoots (canes) that fell over, did they bend over close to the bottom or somewhere higher up?  Is the bend area softer than the rest of the cane?  If softer, that may indicate that it may be infected with a bacterial rot.  If it is soft, it is best to remove the cane completely by cutting it off before the infection spreads to the other canes.  When cutting diseased plant parts, it is best to use a new or sterilized blade to make each cut, continuing to use the same blade without sterilization can actually spread the infection due to the sap on it.  I like to use new single-edged razor blades to cut with, use it once then throw it away.  Industrial grade blades are available in paint and hardware stores and are relatively cheap.  Just be sure you cut the plant and not yourself!!!  (grin)  

Depending upon what type of dendrobium you have, loss of leaves may be normal or not.  Deciduous dendrobiums lose their leaves after about a year while evegreen dendrobiums keep their leaves for a number of years.  You can tell which you have by where the flowers were, deciduous produce flowers along the cane while evergreens produce flowers on a stem grown from near the top of the cane.  If yours is an evergreen type, look at the base of the leafs that fell and if there is a black sooty substance on them, that probably is a fungus.  Fungus grows under moist cool conditions at night, especially if you water or mist the plant late in the day which may not allow enough time for the water to evaporate before night fall.  

With cool weather, it is best to reduce watering.  For deciduous types, do not water through winter but mist the root area lightly to help maintain a little humidity.  Evergreen types should be kept barely moist through winter.  

Lastly, deciduous dendrobiums can easily take temperatures down into the 40F's while evergreens prefer it to be above 55F.  

Hope this helped.  If you have questions about the above or have other questions, write back and I'll try to help with them.  

Jim Kawasaki
San Jose, Ca.