lilac tree which is covered with Bacterial blight and powdery mildew

My new garden has a lilac tree which is covered with Bacterial blight and powdery mildew, and the leaves have holes in them, I would dearly like to get it back to health, please be kind enough to advise me what I need to do.

I also have 2 plum trees next to the lillac which is also suffering from the holes in the leaves.

Many thanks indeed

 

Hi Hamilcar,

Sorry to hear this. Take a look here for id and treatment.
http://plantclinic.cornell.edu/treeshrub/lilac.htm

Lilacs tend to like a more alkaline soil and aren't big nitrogen feeders, so if you have it in a lawn that gets fertilized, that will tend to weaken your plant. I would topdress with compost. Here's some helpful growing info for your lilacs.
http://www.heardgardens.com/basicsforlilacs.htm
http://www.lilacs.com/frames/care.htm
http://lilacs.freeservers.com//lilac_tips.html

Here's some info for your plums.
http://members.efn.org/~bsharvy/edible9.html#PlumEuropean
http://members.efn.org/~bsharvy/edible9.html#PlumJapanese
http://ssfruit.cas.psu.edu/chapter5/chapter5a.htm
http://www.ext.nodak.edu/extpubs/plantsci/hortcrop/pp689w.htm

Newt