We want to add grapes for jelly, rasins and wine making. So I'm looking for the 3 top seedless varieties for zone 6 twenty miles north and much higher than Chattanooga.

I don't grow seedless grapes here. I did in CA. Maybe someone from TN will be along to answer this.

Have you already planted some grapes?

In pots.

How are your grapes doing?

From my research so far, and having grown nearly 50 varieties, I choose Mars Seedless.
Black rot is my nemesis and Japanese beetles are demons.

@Valerie1234 how bad is pierces disease at your place ? In South Carolina it's so bad it's hard to grow anything other than muscadines.