Plants for north facing wall

I have a 12 foot stretch of 4 foot high ugly breeze block wall surmounted by wooden trelliswork. I would like something (preferably easy to look after) to climb/grow in front of the north face of the wall. The area in front of the wall is open but of course gets no sun. Suggestions gratefully received.

 

The most commonly recommended culprits are a winter flowering Clematis - such as Clematis armandii or a climbing Hydrangea (petiolaris)

Would they be any good?

 

Thank you for the suggestions, will put them to the plant choosing committee when she comes in.