I've had a Jerusalem Cherry plant
for about six months now, and by and large it's doing well in my office window at work. It's got a nice distribution of fruit (the 'cherries' of the title) around the upper leaves, but I'm suffering a great deal of yellowing on pretty much all the leaves, along with some black spots. Weirdly, the plant
itself still seems to be thriving, but the yellowness is spreading and I can't figure out why.
I've had a snoop around the internet for likely causes, and most identify over/under watering as probable, but I can't tell which it is! The soil seems to dry out very quickly; particularly at the moment, as the temperatures are picking up in the UK. I've tried fortifying it a bit with some potassium; specifically a banana skin trick my gran taught me, but still haven't been able to stop the spread, and am a bit out of ideas.
Help much appreciated.