Question
QUESTION: My AV is growing and getting new blooms and new leaves but the older leaves have a yellow around the edge of them.  Why??
ANSWER: Bert,
I need more information before I can adequately answer your question.  I am not clear what you are saying about the "yellow edges".  I'll wait to hear from you.

---------- FOLLOW-UP ----------

QUESTION: The leaves are all green except for about 1/8" around the edge of the older leaves that have yellow.

Answer
That still is not a lot of info, Bert!  I will give it my best shot.  Any time AV leaves have discoloring on them is usally a symptom of either temperature change, (usually cold), or water touching the leaves, most specifically cold water.  It doesn't sound like water spots, so I would opt for the cold temperature.  Hope this helps.