Question
Hi,
I was given a phalaenopsis orchid on November 19th as a birthday present. The plant was already in bloom. Two days ago the last white flower wilted and fell off. The plant is quite large with leaves a rich green and has two small leaves growing at the base of the plant. It has two long stems and one of them has a stem growing off from it which did not produce any flowers. The plant is in a clay pot with bark. The end of the stems are still green but about an inch back the stems on my plant has turned a yellow/brown color. The stem growing off from one of the main stems is still totally green. I would like for it to re-bloom. I'm wondering if I need to prun my plant. If so where? Do I need to cut off all of the discoloration? Why would the tip of the stem still be green? Thanks so much for your help!

Answer
Isabelle, the flower spikes on some types of phalaenopsis turn brown and die back. It is possible, if your have a new branch on one of the flower spikes, that it will die back to the branching point only.  Probably the best place to cut the spike is just above the node (ie joint) where it has the new growth. On the unbranched flower spike, cut the spike off just above a node.  If the flower spike dies back, it is in the nature of the plant and has nothing to do with your culture.  Normally, phalaenopsis flower only once per year.  If the plant is large, they may, occassionally, continue to flower by sending out branches which may also form buds and flower. You may grow this plant on for years and rebloom it if you follow the care instructions.  

With regard to your question of the spike turning brown while the tip is still green, the tip of a flower spike contains cells which can form new tissue.  There is a kind of war being raged within the plant between genetic tendency for the old plant cells to die back and the tip of the spike to continue growth. As the older cells in the spike die they will reduce the flow of necessary hormones to stimulate growth at the tip of the spike. I think you can expect die back of part or all of both spikes.  This, however, is not the end of the plant but merely the primary end of a flowering cycle.  It may still do some flowering from a branch at a  node.