Posted: 31/03/2016 at 17:18
It's a very narrow border Natalie, so it's a bit more limited, but there's plenty of things which will be happy there. Perennials - Astilbe, Japanese Anemones, Hostas, Geraniums (the hardy ones, not Pelargoniums) Pulmonarias, Dicentras, Pulsatillas, Heucheras and Tiarellas for starters. Some evergreens to give a bit of background and structure - Pachysandra (low growing) prostrate Gaultherias and some of the variegated Carexes. They'll give you a foil for the other plants.
There are annuals which are happy in shade too - Busy Lizzies in particular - so you could add those for summer. Spring bulbs planted this autumn among those will add some early colour. Crocus, snowdrops and anemones will all be fine there.
You could add some sweet peas for summer - they will do well enough with a bit of shade. Clematis for the fence is a great idea - take a look at Taylor's online site and you'll find loads for that aspect. The alpinas might suit you as they're early and need no pruning. You could then add one or two for summer/autumn depending on how much room you have.