horizontally, and vertically up to about 4 feet? My neighbours at the back decided to take huge chunks out of the ivy hedge. They did this 3 years ago and it's not growing back. Not a problem for them as the hedge on their side only shields a path but from that path they can see right into my garden, dining room and kitchen... I am looking for an evergreen that can live in semi shade and maybe twine along the ivy and hopefully grow up about 4 feet but it's the horizontal that's most important as the existing ivy is much thicker at the top than at the bottom where they've hacked it out.
Try looking at the RHS web-site - they've a "plant selector" section, where all you do is choose what features you need from various drop down boxes and it churns out a list of options. Is really good.