I planted some nice healthy pansies a few weeks back, and they looked
great for a little while. But now, all the flowers look diseased.
I've clipped off all the flowers to start anew, but as they bloom,
they all look mangy, with brown rotten-looking, almost moldy edges.
I've posted a photo at http://www.inhouzemusic.com/pansy.html.

What's causing this, and is there any way to treat the plants without
digging them all up, discarding them, and starting over?

Thanks!