Hi Virginia - it"s a tricky spot as it will probably be quite dry as well as shady. Some ideas could be some of the Acanthaceae shrubs: Mackaya bella, Odontonema (sometimes called red Justicia), or Megaskepasma (Brazilian red cloak); some of the taller cane Begonias or Plectranthus ecklonii, which has purple, pink and white forms and is pretty tough. Give the plant some compost and keep well mulched and watered until it establishes.Deirdre

 I have had some success against a wall in very dry shade with Chines star jasmine, Trachelospermum jasminoides. It has flowered well and has covered an area of about 2.5 square metres. It climbs up a piece of verandah iron that I rescued from a house demolition, and I just tie it in occasionally. When I planted it I put some water crystals in the hole, and I mulch it well. Good luck, Virginia