Yes, you can graft the black tartarian directly onto the bing and vice versa. People do stuff like that all the time.

Neither of those varieties is too hard to find though, so if you lost one of the trees you could replace it or graft it then. I suppose you want two trees both in production with both.

Okay, great. Is there a disadvantage to doing it this way? Would the grafted limb be any better or worse off it was coming directly from the rootstock instead?

Yes, I know both are easy to find. I like the idea of having two self-pollinating trees. Also, it will be my first chance to try out grafting (something I've been anxiously waiting to try). I've read a lot about it and watched many YouTube videos, but haven't had a chance to do it myself yet. So, it's for practice purposes as well.

Doc,

I would not let any sprout from the rootstock to come up at all. Just use a branch on top about a pencil size and graft your dormant scionwoods to it ( use wedge or bark graft). Make sure you rub off all the new growth below your graft union because you want the sap to feed your new graft only.

Good luck.

Tony

Doc:

It would be difficult to graft directly onto the rootstock. At least it would for me. I'd do a whip and tongue onto a small branch higher up in the tree. But I'd chose a location that could by pruning be made to become a significant portion of the top as the tree gets older.

There are many ways to do this. You could try several, bark, cleft, and W&T just for grafting experience.

Ok, thanks for the info. I just want to make sure that I'll get the same results from grafting above the rootstock graft as I would by grafting directly to the rootstock itself.

You'll likely get a better overall result if you follow the advice given and graft the two cultivars directly onto each other instead of trying to perform some sort of exotic graft down below the graft junction or onto a sucker.

For your intents and purposes (the way you are asking) yes, you'll get the "same" results.

But if you are going to get into the excitement of grafting, why not find a friend or neighbor or somebody who has a 3rd or 4th variety and add those onto your tree? That's when the fun really begins.

Yea, I'd love to find someone nearby with a different variety. Haven't yet, but I'm gonna keep looking.

Thanks for all the info!