I have 8ft Leylandii along the outside of most of my west and north facing fences, but there are some gaps on the north side, so I have been using a range of climbing plants inside the fence to provide some privacy, but after seeing some lovely dense cotoneaster covered walls and fences I was wondering whether I should plant them inside the fence at these points.
I live in central Scotland, on clay soil. The fence is a common type - diagonal wood planks with gaps.