Posted: 12/11/2013 at 10:23
Just a thought, but what about a mixed hedge? I planted one some years ago in a previous garden and it looks wonderful. I used a mix of beech, hazel, hawthorn and spindle (euonymus -fabulous autumn colour).
You could leave out the hawthorn if it's too prickly, but it's not very. You could then plant some of the smaller flowered clematis which have wonderful seedheads in the autumn/winter, and they could weave through the hedge thickening it up which would add to the screening effect and look glorious