"Martin Brown" wrote in message
...

I favour pruning about one third to half of all stems out each year
leaving the most colourful and avoiding crossing branches. On poor soils
it is too brutal to take them down to ground level every year and you get
weedy fragile watery stems that break in a strong wind.

Just cut out the parts that have lost their stem colour.

Regards,
Martin Brown

Good post. One of my rules of thumb when working with this kind of dogwood,
or anything else which needs regular heavy cutting in order to achieve a
certain result, is to cut "one in three" stems out. This is one of several
other rules of thirds which keep popping up with us who prune for a living.
As with most rules, it can be bent quite a bit. But in this case, as you
say, only remove the parts which have lost the desired stem colour. Cutting
all of them at one go is quite harsh.