Sorry for butting in but .... 6ft?! Your trellis is hanged on a fence
6ft off the ground?! You need to bring your trellis to 1ft from the
ground and put another to fix above and another above this I'd
imagine.

I think this is just my general lack of knowledge about this sort of
thing.
The trellis I envisioned using is about a foot wide and as long as you
like.
I was just going to nail this to the top of the 6ft fence making the
top of
the trellis about 7ft from the ground and I thought I would be able to
grow
a plant just in the trellis and not have it grow too much down the
fence.
I think I see what you mean though, I have to "train" the plant up
something
(a cane) and then presumably guide it along the trellis a it grows?

I would prefer evergreen and it musn't shed leaves onto my neighbours
land.
The fence runs North-South.