Question
Thank you for your assurance, Jim.  It sounds like it may still be okay even though the spike is yellow.  I live in PA and I originally kept the flower by the south east window, but moved it to the north west window after the flowers started to fall.

I tried to keep the plant fairly dry, but after speaking to my pastor's wife whom has an orchid, she suggested to keep it moist.  I tried watering it a bit more, but shortly after, all the flowers fell and the spike turned yellow.  It's been a week ago since I last watered it and I've just left it alone.

There are 2 huge and healthy leaves and 2 smaller ones, one looked damaged a little.  The roots look okay, though I haven't repot it.  I will be patient and wait to see what happens in the coming weeks.  Let me know if there is something more I can do.  Thanks again and I will keep you posted.

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Followup To
Question -
I bought a phalaenopsis orchid several weeks ago.  Since then, all of the flowers have withered and fell off the branch little by little.  Now, the branch itself is turning yellow.  The leaves look very healthy, but I'm worried that it is dying.  Will it revive?  What can I do to help it along?  I've cut the branch below the last bloom hoping that another branch will form, but it looks so hopeless.  Please help.  
Answer -
Hellow Cindy,

It may be that it just was time for the flowers to die off your phalaenopsis orchid plant.  Phal flowers can last from 8 to 12 weeks, sometimes longer.  Yours may have been already open several weeks before you bought it.  You didn't mention where you live or how you are growing it but here is some basic information regarding your phal.  

Here are some things that can affect the longevity of the flowers.  Any ripening fruits nearby, most fruits give off ethylene gas while ripening which is deadly to the flowers.  Any sudden temperature changes greater than 10 degrees.  Too much direct sunlight, phals prefer indirect sunlight or semi-shady.  A heater or air conditioner vent nearby.  Over or under watering, both will produce the same result.  

As for the branch or flower spike, you can either remove it or reduce its height.  To remove it, cut it off down low or as close to the bottom as you safely can.  If the phal has 4 or more good healthy mature leaves, you can do what you have already done, reducing the spike height to encourage it to produce another or seconday bloom spike off the original.  Did you look for a bump or node along the spike below where the bottom most flower had been, go up about an inch and cut off the top part that had flowers on it?  If all goes well you will see a new spike grow outward from the node and in about 8 to 12 weeks new flowers.  Do this only if there are 4 or more healthy leaves, producing flowers can be stressful to your phal and with fewer leaves, you will see the leaves begin to wilt and even shrivel.  

How often do you water the phal?  Phals love to have moisture around their roots but not constant wetness.  It is best to allow the potting mix to become barely moist between waterings.  Kept constantly wet the roots will soon rot, no healthy roots means an unhealthy phal.  I find the easiest method to decide when to water is to lift the pot, if it feels somewhat light it is time to water but if it still feels somewhat heavy to wait a day or more.  

Hope this helps.  Good luck and good growing.  

Jim Kawasaki
San Jose, Ca.

Answer
Hi again Cindy!  (grin)  

That is one of the misconceptions about orchids, that they need to be kept constantly moist.  While that may be true for some houseplants, it can be a death sentence to many orchids including phals.  Don't get me wrong, as I said, phals do love moisture but not constant wetness.  You are doing the right thing by allowing the potting mix to slightly dry between waterings.  

If given a choice, I would keep the phal near the southeast window rather than the northwest one.  The phal would be happier!  A northwest exposure can become somewhat hot during the summer months, even if it may not feel that way to you.  If you prefer having it in the northwest window location, it would be adviseable to have a small fan going all day to keep the air moving, this will help keep it a bit cooler during the hottest time of the day.  

With only 2 large mature leaves, I would suggest cutting the spike off.  Cut it off as low as you safely can.  It won't harm the phal if there is several inches left, it will eventually turn light brown and become dry.  

Speaking of the smaller 2 leafs, keep an eye on them to see if they grow to be as large or larger than the 2 larger leafs.  If they do not, that may indicate that the phal is not growing well and it needs your attention.  The remedies might be slightly more or less frequent watering, this is the trickiest part, determing which it is.  The easiest way to decide which is to unpot and look at the roots inside the pot, if some or all of the roots are soft and rotten then it was due to overwatering but if they appear to be somewhat dehydrated it is underwatering.  

As an aside, I prefer repotting my phals into fresh mix yearly.  Phals seem to love being repotted.  It is best to do any repotting in the spring or after the flowers have died off.  Another thing, while the visible roots may look fine, the roots within the pot may not be so well.  This is another reason why I repot as often as I do, I can check all the roots to see how well I've been doing in caring for them.  (grin)  Few or no soft rotten roots means I've been doing a good job!  (LOL)  

Have a good day,

Jim