Hard to say for sure with so little info about your culture, but let me
throw these ideas out:

Yellowing of the inflorescences after blooming is not necessarily a problem.

Yellowing and loss of lower leaves is also a normal part of the growth cycle
of a phal.

HOWEVER, as both are happening simultaneously, and as you're losing more
than just a single, old leaf, I'd speculate that you've overwatered the
thing into a condition known as root rot.

The best thing to do is to unpot it, check the condition of the roots,
trimming away old, dead ones, and repot into fresh medium.

--

Ray Barkalow First Rays Orchids
http://www.firstrays.com
Secure Online Ordering & Lots of Free Info!


"Kevin Laurence" wrote in message
...
Our Phalaenopsis 'Happy Girl' is in trouble. After its flowers fell off,
we
pruned one of two stalks. Now the lowest leaves have turned yellow and
fallen off, and both stalks are slowly turning yellow. What are we doing
wrong?

Kevin.