I had a similar problem with my Fatsia, the yellowing leaves were all mildewy and rotting when I removed them. The plant had only been in situ for just over 1 year. I lifted it and replanted it in an area that gets very little direct light. I seems to be coming on leaps and bounds, leaves are nice and glossy and the whole plant looks very heathy.

Thanks for the advice. They may be getting more sun than they should, however, they are probably in the shadiest spot in our yard. Not sure I have another place to put them. Will figure something out. Thanks again.