https://en.wikipedia.org/wiki/Gibberellic_acid
You could even just scrape it and put the brick on it without any thing else if you want.
There are also video that discuss the old timey way of propagating that use willow water.
Bonus!! Here is someone discussing using rock on the branch air layering that I discussed above. (I saw this technique in an old Rodale Encyclopedia of Organic Gardening.)
Ok, but re: the scraping, do you just scrape off the outer bark layer? I’ve never tried that. I have tried just planting the vines, as is, into the soil below where the vines were growing. I’ll try what you’ve suggested this year.
I was surprised at how easy growing the grapevines was. I cut off ten or so dead-looking branches last winter and put them in a pot of dirt outside like it said to do on the internet. I figured, what the hell. This spring I was shocked to see most of them sprouting green and growing.
With the Blue Sky Vine, I just take woody cuttings and leave them in water until I see roots grow, then I plant in Styrofoam cups filled with potting soil. If they grow there, I later pot them and grow in medium sized pots until they are established.
Thanks for the tips.