It seems that for certain fruit like kaki hybrids, it is better to let the grafted hybrid, make its own roots. That should be done, by planting it deeper than the already established graft.

Is anybody aware of such techniques ?

It is said, that such plant is much sturdier than its original. The rootstock dies automatiquely off, after the grafted top has developed its own roots.

Thanks a lot for larger information.

Leo at Flanders - belgium