Some posters may not be aware of the online RHS problem solvers and many
other helpful facilities which they offer free, online.

For instance, if the leaves of your rhododendron have notches in them
you can easily identify the culprit and learn of the cure by following
these fairly simple steps:

Go to http://www.rhs.org.uk/ Advice At Help and Advice select 'Or
try our easy-to-use problem solver' select Problems select Holes and
leaf loss at 'Which part of plant is affected, select leaf scroll
to 'Leaves' and open the links under General until you find the answer
to your problem.

Regards,
Emrys Davies.