Beginning of the annual growth cycle of the grapevine after Hibernation (see also under BBCH Code ). These break at an average daytime temperature of 8 to 10 ° Celsius those eyes (Winter buds) on the winter pruning were deliberately left standing. The winemaker can recognize this for some time beforehand, because with the coming spring and thawed soil, the roots begin to pump plant juice into the above-ground part of the vine so that water droplets emerge at the intersection of cut shoots (the vine "bleeds"). As the heat increases, the buds visibly swell until the woody bud shells break open to reveal a fuzzy globular braid that initially protects the underlying shoot tip from external aggressions such as sun and rain.
By thrusting from below, this white or rust-felted hair fuzz continues to swell, until the green hair of the hair crown becomes new shoot erupts. This is initially still very compact with small leaflets folded over each other, but they spread quickly and become larger in the leaf area, while the shoot goes into length growth.
The exact time of sprouting depends on the macro- and microclimate of the vineyard as well as on the specific characteristics of the vineyard vine from. It occurs in the northern hemisphere from March to April and in the southern hemisphere from October to November. A cold spring can delay the timing and progress of growth by several weeks. Until the formation of new leaves, the vine feeds on the carbohydrate stocks stored in the trunk and roots in the fall. If then the leaves are fully developed, the sugar supply is again via the photosynthesis,
Five to seven weeks after the eye has been released, when a certain number of leaves have been formed by the young shoot, the development of flowering plants for the following year begins in the newly-created leaf-axel buds for the next year. This means the number of bills (inflorescences) of a shoot and the number of blossoms each transaction is already determined in the spring of the previous year. The botanical name for this process is initiation, Even in midsummer, these are dormant eyes (Winter eyes) trained so far that they could drive out, but this is prevented by inhibitors. This can be demonstrated by the following simple experiment: When the shoot tip and the epicormic shoot one Triebes removed, these winter eyes drive out soon after. The next development phase of grapevine after sprouting is the blossom, A list of varietal specific keywords is under grapevine contain.