We use three pairs of wires (catch wires)for our Vertical Shoot Positioning trellis. Our fruiting wire is at 28" , the first pair is above this wire at 12" and next two pairs are again spaced at 12" above the others. These wires are taken down at the beginning season. As the growth of the vines grows, once the vines are 4" above the catch wire position, then we begin putting the wires up. We are currently at the growth of putting the first two wires up.
Moveable catch wires eliminate the labor of tucking the vines in the catch wire system. Additionally, the vines tendrals would have to be broken in order to tuck the vines.
We recommend the VSP system especially for vinifera growing. It is the best system and we are darn happy to have it.