You don't necessarily have to hide the whole fence. I like the idea of creating a small seating area: a bench, chase lounges, a place to read or chat on the phone, a side table for your drink. Maybe a couple rose bushes, honeysuckle vine.

Also think about whether you want to apply a coloured woodstain to the fence. I painted mine with a green one which makes it disappear behind anything planted in front of it.

As the fence doesn't belong to you, you can't paint or stain it as Andrew suggests, unless the owner agrees to it. Drips and runs always end up on the other side, making the fence look horrendous for the owner. If you do it without permission, this constitutes 'criminal damage' and could cost you a heap of money and a major falling-out with the neighbour. If you want a nice-looking fence rather than plants, then your only option is to erect one on your side of the boundary.

What you can and can't plant against this north-facing fence depends on your soil. Bear in mind too that anything you plant must not damage the fence, so shade-tolerant, clinging climbers (such as ivy and hydrangea) shouldn't be considered.

I would have liked to suggest a couple of climbing roses but I wonder whether you will get enough sunlight on north facing aspect. So how about Chaenomeles, Japanese quince. You can set up a couple of posts and wires and fan them out. Beautiful flowers on the bare stems in springtime and fruits in summer. Wonderful selection to choose from.