You could try one of the small flowered clematis, or perhaps two flowering at different times. I had one at our last house that grew well on a north fence, but I can't remember the variety. Check with your nursery which varieties would work.

For something different you could try and get some Codonopsis grey-wilsoni bulbs. The shoots are just emerging now, they will twine up the ivy and produce gorgeous blue flowers in summer. Codonopsis 'Himal Snow' is a white flowered version.
Because the emerging shoots are so delicate that I fear to break them off as they emerge, I grow the bulbs in two litre pots and put the pot beneath my chosen shrub when the shoot starts to grow.

Thanks to Steragram and Bulbaholic for your replies. I tried some Clematis suppliers, but they could not recommend an evergreen variety which would tolerate the cold North winds. Pity cause they are great plants.
Codonopsis - great suggestion - evergreen, frost hardy climber. Can source it no problem - I'll certainly give it a go.

Hi Ken B, you could try an evergreen honeysuckle or a rose for shade like Zephirine Drouhin, although not evergreen it may get the colour you are after.