Woofie: thanks for the advice. I will be careful about watering: my wife does regularly point out that she thinks I overwater the clusia.
WillC: thank you, I will move her closer and see if it helps.
1) I read online that when you prune houseplants you should prune about 10% of it and that twice a year is a good frequency. Does this apply to my kind of Clusia?
2) Does it also apply to areca palms this size:
3) Are there any rule of thumbs or telltale signs for when to replace the soil and when to add fertiliser? Both my clusia and areca palms are in the soil they came in when I bought them at IKEA 2.5 years ago.