My raspberries are 3 years old and this year they are bearing lots of fruit, my problem is that lots of bright orange spots are growing on the upper surface of the leaves. Can anyone give advice I am worried that I may lose the whole crop. Thanks
My canes are around the same age as yours and I had this problem about 2 years back and someone told me it was to do with watering the canes high up (i.e more on the leaves than the ground) when using a hose pipe. Although it looked quite bad the rasberries did come ok.
Last year I made an effort to water at the base of canes and I didn't have the orange spots - could be a coincidence though.
It might be a fungal disease called 'rust'. It won't harm the fruit, but after harvesting I would cut the affected canes down and burn or cut them up and throw them in the dustbin (don't compost them.) If it is not on all of the leaves, try picking off all the affected ones and disposing in the same way. Also don't water from above as this could transfer the spores to new shoots emerging from the ground (ie next year's canes.)