I have an unhealthy star jasmine. It is about 12 - 15 years old, and for most of that time was thriving in an old wooden barrel. About 4 years ago we transplanted it into a custom built, sturdy large wooden box. It has never been the same since. The first signs of trouble were that a lot of its leaves started getting spots, turning red, then brown, then falling off. This year it has been infested with small white fuzzy looking pests on the underside of its leaves. (see photo) I thought they might be woolly aphids, or mealy bugs? I've also noticed a few scale insects on it. Any advice appreciated.