This phal just finished blooming today. When I bought it, it was
crammed into a very small pot. There was almost no growing medium,
but it had gorgeous blooms and was doing very well, so I decided to
leave it alone until it finished blooming.

I noticed today that the base of the leaves is turning black. What
should I do? I haven't repotted it yet.

Photo is he http://home.comcast.net/~jbcamel/orchidproblem.jpg

thanks.