shot hole disease in prunus
 

One of our weeping cherries is badly affected by this shot hole fungus
and I gather the best time to spray will be just after leaf fall - but I
don't know which fungicide would be best. Would anyone have any ideas?

Also, I think we may have exacerbated the condition by pruning the tree
in winter a couple of years ago. It needs some pruning now, and it is
still in full leaf, but presumably the only safe time will when the sap
is rising in spring?

Thanks!

--
Klara, Gatwick basin