Yellow leaves - help!!
I have a Sorbus aria which is around 3 yrs old and the leaves in the centre of the tree are all going yellow/brown and falling off - see pic. The tree is in quite a shady area although it does get Sun most of the day. I also have yellowing leaves on some of my other plants nearby - a solanum and honeysuckle.
Do you think this is a soil problem - is very alkaline when I tested it? If not, any ideas what could be the cause?