We've just had a new patio laid yesterday - one side faces the house and the other looks down towards the trees at the bottom of the garden, but in order to make it private we're going to have to run some kind of screen down each side because we're very overlooked by the neighbours. The patio is a rectangle and the sides are only 8 feet long, so luckily we don't have a huge area to screen off. We're planning to use 6ft high trellis but rather than mess about with fence posts, we're going to screw it to the back of some wooden troughs like this, making it freestanding. The troughs will face outwards towards the garden, with the trellis on the patio side.
The trellis itself will give us plenty of privacy, but we'd like to grow something up it to make it look more attractive. The garden is south facing so each trough will get direct sun in the morning or afternoon (depending which side it's on) plus sun from the south all day. Obviously soil quality isn't an issue (which is another reason for the troughs - our soil is rotten!), but it'll need to be pretty hardy because we're in Scotland near the coast. I'd prefer something evergreen that would give us some flowers in the summer - but this isn't essential so long as it will start covering the trellis quickly without becoming too dense.
Any ideas?