Last stage (also leaf fall) in the annual vegetation cycle of the vine after maturation = ripening phase (see also BBCH code). In botany, the shedding of leaves, fruit and other plant parts such as leaf and flower buds, twigs, spines, thorns or inflorescences is known as abscission. In the northern hemisphere, leaf fall takes place from November to December, in the southern hemisphere from May to June. In temperate latitudes, leaf drop 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, the annual wood can lignify and mature for winter dormancy and sufficient reserves of carbohydrates (starch) can be stored in the trunk and roots before growth is stopped.
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