Question
I have a phalaenopsis orchid that grew a second stem.  The second stem also grew a branch and both the new stem and its branch recently bloomed, while the original stem remained flowerless.  I lowered the room temp to about 60 when I went out of town and came back to find my stems yellowing and my flowers drooping.  Did the temperature change hurt the blooms, or was it because I should have separated the second stem from the original?  What can I do to revive it?  The yellowing is slowly increasing and is now about a foot from the leaves.

Answer
Alison, thanks for your question.  It is possible that the sudden change in temperature had some effect on the second flower spike by shortening the bloom period leading to early flower and bud loss. This may also be the result of drier air about the plant at cooler temperatures, especially in the winter months.  Cut the yellowing flower spike below the area that is yellowing, but above a node (ie joint) in that flower spike.  It may stop yellowing above that node.  If it continues to yellow, you may cut the entire spike off where it emerges from the leaves. It is difficlut to know at this time whether your phalaenopsis is the type that retains its green flower spike.  If it is not, you will experience yellowing and die-back of your flower spikes-- that is natural for that type of phalaenopsis and shouldn't alarm you. A healthy plant should rebloom on a new flower spike next spring.

Speaking of a healthy plant, be sure to repot yours now that it has finished flowering. You can obtain orchid potting mix at a nearby garden center. Try to get the type that contains fir bark.  Also be sure the pot used for repotting has lots of drainage holes in the bottom and/or sides.  Soak a portion of the new potting mix you plan to use before you unpot your plant.  Rinse off the roots and check for any collapsed roots before repotting. The fresh potting mix will give your plant a fresh start for the next growing season and is recommended following each flowering.