At what time should the graft be inoculated and at what time with the kidney? why?

Grafting with cuttings (they should be at rest) should be carried out in the spring, until the buds have started to grow, and the air temperature is still low and there is sufficient humidity (this prevents the rootstock from drying out). The best time for grafting with a bud is the second half of summer, when the plant has already developed a one-year shoot. This is explained by the fact that the grafted part and the trunk grow together, and the shoot has time to prepare for wintering.