I have a healthy raspberry plant in its second year of living on my balcony. It's been producing a decent amount of fruit and has grown new canes, ready for next year. However, in the last week or two some of the leaves have started to turn yellow then brown in the middle. It doesn't seem to be leaf curl, or lack of watering (from my limited knowledge of raspberries).
Does anyone know: a) what is the problem, and b) how do I solve it? Should I cut the browning leaves away?
- The plant gets sun from morning to mid-afternoon (balcony is south-east-facing).
- I live in south Germany where the summers are hot (average 25-30 deg C).
- Last year it lived in a slightly shadier area, and I didn't have this problem.
- Its pot is about 40 cm deep, but I water it often and the roots look fine.
- There appear to be a few weevil-type bugs on the plants; Google suggests they might be vine weevils.