Plum Trees

Hi all, 6 months ago I moved to a new home with an orchard, I have never had fruit trees before so its all new to me. The apples and pears are doing great, but the plum trees are not. The leaves are full of tiny holes and the leaves and fruit are covered in dry brown patches. Can anyone tell me the cause of this and what I could do to hopefully cure it for next season.
I guess they have never been pruned or cared for for a few years.

 

You really need to get yourself one of the RHS books on Fruit tree growing and pruning and pests and diseases. There are an awful lot of things to know about looking after fruit trees.
For example brown patches and holes in leaves could be Bacterial canker, in which case removal of the affected trees is the only answer. BUT is could just be one of the many forms of rust and insect damage. On the fruit itself it could be Brown rot, which is very common this year. Remove all affected fruit and burn or bin, do not compost.
Sorry not to be able to help much more than this.