Last stage (also leaf fall) in the annual vegetative cycle of the vine after maturation = ripening phase (see also BBCH code). In botany, the shedding of leaves, fruits and other parts of the plant such as leaf and flower buds, twigs, spines, thorns or inflorescences is called abscission. In the northern hemisphere, leaf shedding takes place from November to December, in the southern from May to June. In temperate latitudes, leaf fall is usually initiated by the first night frost. Ideally, leaf loss should occur some time after the grape harvest in late autumn. Then the leaves can still produce carbohydrates, lignify and ripen the annual wood for hibernation and store sufficient reserves of carbohydrates (starch) in the trunk and roots before growth stops. Each grape variety requires a variety-specific minimum duration of the vegetation period in order to achieve permanent grape and wood ripeness. In frost-free areas, some leaves can remain on the shoots until early spring. After the leaves fall, the vines are left dormant for the winter, during which the vegetation cycle starts again after Rebschnittpruning when the buds on the annual shoots bud.
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