Rootstock ONLY is just what is says; “rootstock only.” There is no grape variety grafted to it. Use this option if you want to do your own grafting in the field.
This is a great option for shade arbors also. Rootstock varieties produce little or no fruit. But, they look just like a fruiting variety without the maintenance and care that comes with producing fruit.
Rootstock varieties are also Pierece’s disease resistant.