Tropicals & Tender Perennials: Yellowing leaves on bottom of vine, 1 by Lilyofthenight

Lilyofthenight wrote:
Hi all, new here. Love the site...anyway. I have one passion vine I purchased a couple months ago. It is in a large wooden pot with great drainage. My mom said not to overwater it, so I have been very careful not to. However, after having around 10 blooms a day for weeks, now I have none. The leaves at the bottom of the vine are turning yellow and falling off and growth has slowed. It's a purple variety, (sorry new here) and I am not sure of the name. Am I under watering? It sits mostly in the shade and has a trellis to climb on. I sure don't want it to die. Only the bottom of the vine seems to be affected.
Here is a pic of it. And any id info will be appreciated.
Thanks!

~~Peace~~