Keyword: Thin out
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Reduction in the grapes as a quality improvement measure in the vineyard, the vert as thinning, BehangausdÃ¼nnung, green waste and green harvest, as well as queen Vendange (green harvest) or Ã‰claircissage known. The reason is that high yield and high quality grapes are mutually exclusive. The removal of grapes is an increased accumulation of various substances into the remaining grapes Vine achieved. The effects are increased extractives, greater weight must , optimization of the leaf-fruit ratio, greater color intensity for red wine and better resistance to drought. Apart from the general increase in quality can be attained by thinning, especially in young plants a positive long-term effect, because they can develop much better.
Of course you can also have the pruning by restricting to a small number of eye achieve a reduction. An extremely strong gate, however, carries the risk of unanticipated adverse environmental conditions during the growing season as late frost or weak Bloom a drastic reduction in yields. Further points of the vine with small bleed on fewer sheets. Therefore, the thinning in the summer, the best possibility of yield reduction, since even many risks no longer relevant and to estimate expected returns are good. A desired yield can be calculated using the following formula: average number of grapes per floor x average grape weight in kg x number of floors per hectare, the yield is in kg / ha.
The time varies depending on the desired result. Earliest possible so when the berries have reached pea size. It is, however, no significant yield reduction. Ideal is the beginning of the ripening period and veraison , because then a necessary distinction between mature and less mature grapes is easily visible. This is usually the period late July to early August. At best, the selective removal of grapes with proven maturity gap. In general, these are the highest grapes on the vine. A commonly used form is the lowest leaving the cluster per Shoots . Up to 50% of the grapes mass is removed.
As a rule of thumb is that 50% fewer grapes "only" about 25 to give 40% yield reduction. The grapes remain mostly on the vineyard floor and serve as the ground Compost . Sometimes they are removed from phytosanitary reasons (prevention of diseases caused by bacterial decay). Increasingly, they are also for the production of Verjus (Juice of unripe grapes) were used. As an alternative to be manually intensive thinning growth-regulating Gibberellins (Plant hormones) are used. Another form of thinning is the division Grapes , here are the still green grapes cut in half. See also Engine thinning and Shoots cut .