The success of simultaneous cutting and grafting is cost effective. In practice, the scion consists of the cultivar stem taken with one leaf and a dormant bud. The scion is grafted on a single internode of the non-rooted rootstock. Formation of the graft union and of adventitious roots on the rootstock occur simultaneously. The combined process takes three weeks.
Air layering involves the wounding the stem of the plant while it is on the stock plant.
Treat the stem then cover it. Roots form in the covered area. The tip of the stem sticking out of the covered area will continue to grow. It will soon become a new plant with it's own roots. The roots form at the wound.