Question
Thanks for the reply.

Is there anything else that will indicate which one? The leaves are narrow and only about 3" to 5" long. They are few in number and there is a lot of cane like stem between them. There are about 5 flowers in each spray. The flowers are only about 1" to 1.5" across.
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Hi

I have been given a Dendrobium Orchid but do not know which type it is, as there is no other name on the label. The flowers are an even color, dark purple, and grow on long very thin stalks(?). I understand that there are three types on Dendrobium, each requiring different treatment. Is there any way of finding out which this one is?

Many thanks
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From your description, you have a either a phalaenopsis type of dendrobium or a New Guinea type-- the latter is a smaller plant in growth habit. These are both warm growing types.  When not in growth, this plant should be rested with very little, if any, watering.  Only water and feed when in growth.

Answer
I think I know the type of denrobium you are referring to.  They are mass marketed in many places including some grocery stores.  I have never seen a name on any of them.  Flowers vary in color from white to lavender and many shades in between.  Dendrobium phalaenopsis orchids genrally get quite tall and have few canes so I'm inclined to belive that these mass marketed plants are hydrids created from New Guinea species or species native to that area. If there is any tag that indicate the nursery of origin, that might provide a clue to the hybrid. Dendrobium biggibum is a frequently used species to produce these miniature plants.