Wine Arcana

Grape

Sousón

Also known as Vinhão, Sousão, Souzão

Sousón is a dark-skinned Vitis vinifera variety of northwestern Iberia, grown in Galicia under its Spanish name and in northern Portugal principally as Vinhão. It combines two properties that do not always travel together in a red grape: abundant colour and pronounced acidity. This makes it especially useful in the multi-grape reds of Atlantic-influenced Galicia and the Vinho Verde region, where it can deepen a blend without sacrificing freshness.

Its colour is more than a visual curiosity. Sousón can give a relatively pale, fragrant partner such as Brancellao a darker frame, or add both pigment and tension to a blend led by Mencía. Varietal wines also exist, but they expose the same balance directly: fruit must ripen far enough for tannin and acidity to feel integrated, while extraction must be controlled so that colour does not arrive with unnecessary hardness.

One vine, several names

Genetic comparison identifies Galician Sousón as Vinhão, the prime name used by the Vitis International Variety Catalogue.[1] The two names therefore describe regional identities of one cultivar rather than similar Spanish and Portuguese grapes. Older Galician names include Retinto, Tintilla, Pazao, and Viñón.

Portuguese terminology needs more care. Current Vinho Verde rules list Vinhão under code PRT51902 and recognize Sousão as its synonym, while listing Sezão separately under PRT51901.[2] The spelling Souzão is also widespread, particularly outside Portugal and in writing about the Douro. A familiar name on its own is consequently weaker evidence of identity than a genetic record or a modern official variety code.

The exact birthplace is not documented. A maintained Portuguese reference finds names associated with Vinhão in Minho sources from 1790 and the present name in the nineteenth century. Galicia's viticultural station traces Sousón, Retinto, and Viñón in several Galician districts to a 1914 survey. These records establish a long history on both sides of the modern border, with earlier documentation presently known in Portugal; they cannot locate the original seedling.

Vine and Atlantic season

Sousón ripens late. That long cycle helps explain its acidity, because the grapes can remain relatively acid as sugars and skin compounds develop. It also creates risk. In a cool site or difficult autumn, harvest may be forced before tannins settle; in a warmer, well-exposed parcel, the same variety can reach greater sugar and phenolic maturity while retaining a firm acid line. “High acid” is therefore a useful tendency, not a promise of identical balance in every wine.

The vine has medium to strong growth and can crop regularly, depending on plant material and site. Galician observations report moderate sensitivity to downy mildew, powdery mildew, and botrytis, while Portuguese records describe some tolerance to the two mildews. These accounts are not necessarily incompatible: disease pressure, clone, canopy density, and the standard of comparison differ. In the humid northwest, airflow and sound fruit still matter for a late grape that may remain exposed to autumn rain.

Vinhão is also reported as vulnerable to drought stress and sunburn. Its association with rainy Atlantic districts should not be converted into a general claim of climatic toughness. Moving inland can assist ripening, but hot exposure and limited water introduce different constraints.

Why the wines are so dark

Anthocyanins are the red, purple, and blue pigments extracted principally from grape skins during fermentation. Sousón accumulates a large quantity of them in its dark blue-black skins, and Portuguese descriptions also record some pigment in the pulp. It is not uniformly red-fleshed like a classic teinturier grape, but the combination gives it unusual colouring capacity. A two-year comparison of 27 red varieties grown at one Portuguese site placed Vinhão among the high-anthocyanin varieties, while also finding that its total changed substantially between years.[3] Genetic potential is strong; season still changes what reaches the cellar.

Colour and acidity arise from different parts of berry development, so one does not cancel the other. Galician and Portuguese institutional records both describe wines with intense violet or red-purple colour and high natural acidity. Less mature fruit can make the acidity and tannin feel severe, while warmer conditions or a later harvest may bring more alcohol and breadth. Selective references to dark fruit, herbs, or balsamic aromas are useful, but no fixed descriptor set follows from the grape name.

Winemaking determines how much of the available pigment and tannin appears in the wine. Longer or more active skin contact generally extracts more, while gentler handling can preserve colour without maximizing grip. Malolactic fermentation softens the sharper malic component of acidity, and maturation changes both tannin and pigment. Deep colour is therefore a capacity of the fruit, not proof that every Sousón wine was heavily extracted or will retain the same purple hue with age.

Blending across the border

In a Galician blend, Sousón often acts as a structural component rather than a neutral darkener. Alongside Mencía, Brancellao, Caíño Tinto, and other local grapes, it can supply colour, acidity, and tannic definition; its partners may contribute a different aromatic emphasis, softer texture, or earlier ripeness. The proportions cannot be reduced to a standard recipe, because a small addition of very pigmented fruit may be enough in one vintage while a cooler year may make its acidity more conspicuous.

The same logic operates in northern Portugal. A Portuguese varietal reference specifically recommends Vinhão for blending with lower-colour Borraçal, the Portuguese name for Caíño Tinto. Vinhão is also capable of traditional red Vinho Verde as a varietal wine, so “blending grape” describes a common function, not a biological limitation or a lower tier of wine.

Its legal geography reflects this cross-border role. As of July 2026, Spain's agriculture ministry listed Sousón as a principal variety in all five Galician protected denominations of origin: Monterrei, Rías Baixas, Ribeira Sacra, Ribeiro, and Valdeorras.[4] Portugal's consolidated Vinho Verde rules authorize Vinhão throughout the denomination and in each of its nine named subregions. Authorization indicates where the grape may be used; it does not require it, prescribe a single blend, or guarantee that plantings are equally important across those regions.

Sources

  1. Ángela Díaz-Fernández et al., “Screening of Galician grapevine varieties by SNPs, phenotypic traits, and phytopathology,” Frontiers in Plant Science 15 (2024), table 1. ↩︎

  2. Comissão de Viticultura da Região dos Vinhos Verdes, Regulamento de Produção e Comércio da DO “Vinho Verde”, consolidated August 2024, annex II. ↩︎

  3. Miguel Baltazar et al., “Characterization of the glucosylated anthocyanin profile of 27 red grape (Vitis vinifera L.) varieties grown in Portugal: insights for climate change adaptation,” Frontiers in Plant Science 16 (2026), discussion. ↩︎

  4. Ministerio de Agricultura, Pesca y Alimentación, Variedades de uva autorizadas en las Indicaciones Geográficas de España, 9 July 2026, pp. 29–31. ↩︎