Hi Peter,
This is known a leaf spotting. It is a fungal problem. Cut off what you can and spray with Mancozeb. Good luck, Dee.

Hi. I am new to the site and found it through a google search.

I have three large hebes in the garden which have done well for about ten years. I recently noticed that they all show signs of die back, one of them quite badly and i doubt whether they will survive. they were fine in the recent dry hot weather but seem to have deteriorated since the recent downpours although they are on three seperate sites which does not become waterlogged.

I was wondering if anyone else had experienced this problem. The leaves and stems simply turn black then the leaves fall to the ground. It seems strange that three seperate plants have been affected and I was wondering if there are any specific new diseases around.

Any comments would be appreciated