Question
Hi,
My dendrobium pravit has recently experienced new growth.
A new can shot up within the last 2 months and is about 6 inches tall. It doesnt have any flowers, and I am noticing that the new stalk and black spots on the cane and on the underside of the leaves.  What could be causing the black spots and what can I do to prevent them?  I water the plant once a week at about 8 in the morning.
Also, the 3 older original canes still have nice green leaves with no black spots, yet these canes are drooping quite a bit.  Three new stalks started to develop about  7 months ago, and then stopped.  They are about 1 inch in height.  I dont understand why these started and then stopped growing, and then months later a new stalk grew, is now 6 inches in height, but has black spots.
This plant has never produced any flowers.
Any advice, please help?

Thank you,

Alex

Answer
There is no registered hybrid or species by the name of pravit.  On many labels, a name is often mispelled, or difficult to read or both.  There is a registered Dendrobium Praneet, but can't be sure this is the correct name.

One of the main problems encountered in growing of dendrobiums is the failure to provide a rest period.  After the plant has flowered, watering should be withheld or greatly reduced.  When this is not done, the plant continues to put out new growth and often this new growth is smaller and, eventually, the plant declines.  You also may have a fungus infection (the black spots) from overwatering.  I suspect that you have some root rot responsible for the drooping canes.

I recommend that you get some fresh potting mix, remove the plant from its pot, clean the roots, and remove any roots that are mushy or in poor condition.  Repot the plant in orchid potting mix in as small a container as you can get it into (probably a clay pot) and withhold all water but morning misting.  You can try spraying the plant with a copper base fungicide or just remove the growth with black spots.  You want this plant to think it's time to rest and nothing to cause it to think that its time to start growing.  It needs to start new growth on its own when it is time.  When it does start growing, feed it and water it heavily only in the morning a couple of time a week.  When you repot the plant, be sure it is firmly in its pot and tie it to bamboo stakes, use rhizome clips, and other means to keep it firmly in its pot.  If and when new growth emerges on its own, you also can increasee light levels gradually.  I suspect that you have a warm growing dendrobium so don't let it get below 60 degrees.