Richard Savage wrote:

Do you mean that I can only prune it while the dead leaves are still on the
branches? Presumably this is before this years buds start to appear??

No, not at all, but it saces on clearing up. :-). I read somewhere a while
ago that the best time is March - logical because you catch them before
they start growing (except this year of course!) and you chuck the leaves
at the same time - and September, because they'll be due for a good tidy up
by then. I stick to this because it works for me. Hard-ish prune in March,
tidy in September.

Cutting that far back is, I assume, a long way beyond (i.e. closer to the trunk)
last years growth?

I my case it is. What I've learned is that if you leave it for a year
without a hard prune it's much harder the following year. In fact, my hedge
is at the stage where I can't do anything with a hedgetrimmer other than
tidy it in September. Loppers are needed for anything more radical.

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