Regarding wine colour, see under colour.
In viticulture, colour plays an important role in various areas. This begins with the soil in the vineyard, which influences the growth of the vines, and continues with the colour of the foliage and the colour of the grapes, which has a direct influence on the colour of the wine and is also very important in wine evaluation.
The colour of the soil provides information about its composition and has a considerable influence on growth and wine quality. For example, a reddish soil colour indicates iron content. This soil, known as Rotliegend or Terra Rossa, is particularly suitable for red wines. See a complete list under soil type.
Unusual discolouration of the leaves during growth indicates a lack or excess of nutrients and leaf diseases. A common disease, for example, is chlorosis, which is characterised by yellow discolouration of the leaves. This means that green chlorophyll is no longer produced in the leaves and the plant can no longer photosynthesise.
The ripening phase of grapes during the annual vegetation cycle is known as véraison. It begins with the discolouration of the berries, which acquire their final colour by the time they are fully ripe. A distinction is usually only made between white and red grape varieties. The criterion is whether the grapes are suitable or used for the production of red wine or rosé (red variety) or white wine (white variety). However, there is a wide range of colours ranging from white, yellow, green, grey, brownish, pink, red, violet, blue and black. Table grapes or ornamental vines are divided into white, red and blue (black) varieties. The berry colour plays a role in the purely visual determination of grape varieties based on morphological characteristics; see MolekulargenetikMolecular...
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