The higher you go, the less effective your suction will be. I have mine run along the wall just below the height of my work tables. Works great, is out of sight, yet easy to reach if there's ever a problem.
I have a section of my gardens I enclosed with fencing. I made it 8' tall. The bottom half is small metal gid that is buried 10" into the ground, the upper half is cables stretched between posts, spaced about 3" apart. It has been incredibly effective. Next spring I'm going to do something...