United Kingdom 
I have a mock orange bush - about 10 years old, which until this year (when it has an abundance of buds) hardly ever flowered, but I believe that is not unusual. It also can get infested with black fly which I have to wash/cut off - depending how bad (as I don't use insecticides), but then we have had many a ladybird larva feeding from that so no big deal. However, now a lot of the leaves have suddenly, over the last couple of days, developed thin brown patches - as if it has been attacked by some sort of leaf miner insect - but I can't find anything out about this in any of my 'what's wrong with my plant' books, nor generally on line. Does anyone have any ideas/suggestions?
Thanks
28 Apr, 2011
Answers
Thanks for your reply, we are organic in our garden, and I don't know of anyone doing anything nasty nearby although it is possible. Again, it has been very dry...
Thanks
3 May, 2011
Maybe drought then. I have seen that type of damage when a plant suffers one severe wilting episode, rather than continuing moderate drought stress. Horticulturalists call it "mesophyll collapse", but that's just a description of the damage itself.
4 May, 2011
It looks pretty typical of chemical damage, Rochelle. Have you or a neighbor had anything power washed nearby? the strong soaps often used can have this effect. It may also be drought damage, though that usually starts from the tips and edges of the leaves.
30 Apr, 2011