I wanted to provide an update on this thread.
I made 6 grafts in total from 2 rare cuttings (Oro, Sangue Dolce) with 3 nodes each.
I treated 2 out of 3 of the scions with IBA.(total 4) Third one of each kind was untreated.(total 2)
I made 2 other grafts on the same day (Genovese Nero, Hative D’Argentuiel). I used IBA on them both.
I now have 5 out of 6 grafts in set 1 budding out. Both grafts in set 2 are budding out. Only one graft hasn’t yet budded out. It coincidentally happens to be the one that I didnt use IBA on. But it may still make it. I dont see a bud on it. It may be latent or may have been non existent. If there was no bud to start with, maybe it would have never made it anyway and the test is inconclusive.
The 4 IBA treated scions also appear to be further along than the one other untreated that also budded out
At a very minimum we can conclude that IBA does not harm the graft and might even be beneficial.
Further, It seems that scions treated with IBA might take faster than those untreated ones.
Another datapoint:
I made one graft a month ago and then another of the same variety (Genovese Nero AF). The scion wood pieces were even cut out of the same original cutting with a 15 day gap between them. The newer GN-AF graft appears to have caught up to the one grafted earlier. But it is still early.
I will provide pictures in a future post.