Learn about wine
Médoc: the magic of terroir
Médoc is without a doubt one of the two or three best-quality winegrowing regions in the world. This level of excellence is not the result of chance. With its small number of fantastic grape varieties and the experience gained over three centuries by its prestigious estates, Médoc also, and perhaps primarily, owes its character to its exceptional terroirs. Like other geographical labels such as ‘the Southwest’ or ‘Champagne’, the name Médoc designates a varied area. In terms of geography, it is a triangular peninsula wedged between two bodies of water: the Gironde River and the Atlantic. In fact, its name comes from the Latin medio aquae, which means ‘between the waters’. The base of the triangle, just north of the city of Bordeaux, is 60 kilometres wide. To travel to the northern tip – the Pointe de Grave – requires a journey of 100 kilometres, at the end of which you find yourself at a dead end, with no option but to turn around or wait for the ferry to take you to Royan, on the other side of the estuary, a trip of about a half-hour. As it is said, ‘You don’t pass through Médoc, you have to go there.’
15,000 hectares of vineyards
The entire Médoc triangle does not lend itself to winegrowing – far from it. The western part, basically all that lies west of the secondary road that links Bordeaux to Soulac, is a forested area of maritime pines that grow in sandy soil, stretching north from the Landes. The peninsula’s northern point (north of Saint-Vivien, more or less) and also the eastern fringe along the Gironde consist of marshland that has been drained to a lesser or greater extent depending on the zone and is used for grazing cattle and sheep. Pauillac, for example, is famous for its lamb as well as its wine. The winegrowing area of Médoc is rather limited as a result. Of the Médoc triangle’s total area of 240,000 hectares, vineyards cover only a bit more than 16,000. The winegrowing area is traditionally divided into two subregions, corresponding to two regional appellations: Médoc (previously known as Bas Médoc) in the north, and Haut Médoc in the south. The latter, the closest to Bordeaux, includes six village appellations, whose very names hold tantalising promise for wine enthusiasts: Pauillac, Margaux, Listrac, Moulis, Saint-Estèphe and Saint-Julien. The main characteristic of Médoc’s vineyards is that they extend over a long, narrow strip of land no wider than 3–4 kilometres in places, and their second feature, not so obvious at first glance, is that they are highly fragmented.
25 metres above sea level
Everyone agrees that Médoc wines owe a large part of their character and uncommon quality to where they are grown. This terroir is unique in the sense that, compared to other highly reputed winegrowing regions in France, it is located at very low altitude. In Burgundy, the grand cru vineyards are on the upper part of the slope that climbs up the Saône Valley almost to 200 metres. In Champagne, the best crus cover the sides of the Montagne de Reims, the Côte des Blancs and the Marne Valley. Not to mention Alsace, Jura or northern Côtes du Rhône, where the slopes are sometimes so steep that tractors cannot access them. The situation in Médoc is totally different. The highest point, in the village of Listrac, is only 43 metres. And this is an exception – the large majority of the vineyards are found between 10 and 25 metres, and descend as low as 5 metres at Ducru-Beaucaillou and Léoville-Las-Cases near the village of Saint-Julien.
So we need to look elsewhere to discover the secret of the Médoc terroirs. Its trump card is its very special geology: gravel mounds that provide the vines with exceptional conditions, resulting in grapes, and thus wines, of superior quality. We should remember that first and foremost, grapevines are plants with very specific water requirements. As is well known, the quality of a harvest relies mainly on the quality of the summer, the season in which the grapes mature. If the soil is thin, its depth restricted by an impermeable layer that does not allow excess water to drain off, the vines risk shocks that are detrimental to their metabolism. During rainy summers, the water will stagnate and potentially drown the roots. Grapes that receive too much water will swell and become diluted. In the event of a prolonged drought, as in 1990 or 1995, this type of soil also carries the opposite risk of completely drying out, preventing the normal development of the grape berries. Above all else, vines suffer in soil that alternates between saturation and desiccation.
On the other hand, if the soil is deep and drains and filters well, it acts as a regulator. Heavy raine infiltrate deep into the ground or run off the surface. This type of ground never totally dries out. The vine roots, which sometimes grow down to a depth of 5 metres or more, can always find a bit of moisture, enough in any case to allow the plant to complete its growing cycle smoothly. All of these favourable conditions are met exceedingly well by gravel mounds. They account for why, in the best terroirs, the renowned grand cru and cru bourgeois vineyards, quality is always present, in every vintage. Understanding how this gravel was deposited, and then how it was shaped into mounds, supplies the key that explains to a large degree the quality of the region’s crus.
A land of gravel
The graves of Médoc consist of pebbles, stones and gravel of various shapes and sizes. The largest stones can be over 20 centimetres in length and weigh more than 1 kilogram, but these are rare: most are 15–80 millimetres. Mixed with finer particles of clay, sandy grit or limestone, they are piled up to a thickness of several metres, sometimes more than 10 metres deep. This gravel was deposited at the end of the Tertiary period and during the Quaternary period under very different climatic conditions than those of today. Generally speaking, the older the gravel, the higher the proportion of finer particles (as the ‘old’ gravel, dating from the end of the Tertiary period, has had more time to decompose), and the less the ground acts as a filter. These soils are mainly found in the northern Médoc, an area that has no cru-classed vineyards. On the other hand, Haut Médoc has better geological luck, particularly in the area containing the village appellations (for example, Margaux, Pauillac and Saint-Estèphe), possessing more recent gravel that was deposited at the beginning of the Quaternary period and so is better preserved. The pebbles here frequently reach several centimetres in diameter, some over 10 centimetres, and provide the vines with extraordinary growing conditions.
When the gravel was initially deposited, it formed horizontal layers, whereas today’s landscape features undulating croupes, or mounds. The reason for this is the terrain. Looking at it closely, we can see that the mounds are separated, dissected by small streams flowing to the Gironde. In fact, the greater the difference in gradient and the more numerous the streams, the more frequent and well defined the mounds. It is no coincidence that this is also the location of the most prestigious cru vineyards. The terroir of Château Margaux, classed as premier grand cru, is a good example. Located very close to the Gironde (its park extends in part along the marshland), the vineyards lie over a series of small mounds that vary between 8 and 18 metres high. The same thing is true of the terroir of Saint-Julien-Beychevelle, where the gravel layer, 5 kilometres in length and 3.5 kilometres in width, rises over the marshland of the Gironde to the east and the marsh and stream of Beychevelle to the south.
It is not surprising that the estates with the best reputations took possession of the edge of the graves, where the relief is more marked: Branaire-Ducru, Gruaud-Larose and Lagrange to the south; Beychevelle, Ducru-Beaucaillou, Langoa and the three Léovilles (Barton, Las Cases and Poyferré) to the east. The village of Pauillac, with its 18 classed crus (of which three are premier cru), is even more blessed by nature. Not only, as at Saint-Julien, does the gravel crest overhang the marshland to the east and the stream of Breuil to the north, it is also bisected by the valley of Chenal de Gahet. This results in very uneven relief and numerous croupes.
To conclude, Médoc’s terroirs stand out according to two main criteria: firstly, the depth and characteristics of the gravel layer; and secondly, how this layer has been sculpted by streams into mounds, which are more pronounced in some places than others. Of course, terroir does not explain everything. As always, other factors are fundamental: the age of the vines, the yield, the methods used for wine cultivation and production ... Nonetheless, it is clear that the most prestigious wines benefit from a geological bonus that most other terroirs are hard pressed to match.
The grape varieties that make Médoc
Médoc produces only red wines (the few whites, some of which are made by top estates, only have the right to the generic Bordeaux appellation). All of its varieties are dark grapes with clear juice.
Cabernet Sauvignon: This variety matures rather late (always after Merlot). In Médoc, it has found its perfect terrain. Predominant almost everywhere here, it monopolises more than two-thirds of the surface area of the peninsula. Cabernet Sauvignon is low in sugar and produces tannic wines endowed with an exceptional ability to age. When young, it is known for its characteristic aromas of blackcurrant.
Merlot: This is an early-maturing variety that produces large, bluish, less densely clustered grapes than Cabernet Sauvignon. Because of its early ripening, it is more susceptible to spring freezes and the failure to set fruit. The wines it produces are powerful and smooth, with good structure and aromas of ripe fruit. It perfectly complements Cabernet Sauvignon. The amount of Merlot that is grown, generally low in Haut-Médoc, increases as you move north.
Cabernet Franc: Also called Bouchet, this variety plays a secondary role in Médoc. Ripening earlier than Cabernet Sauvignon and also less tannic, it brings a touch of subtlety and the soft aroma of red fruits to a blend.
Petit Verdot: This variety is even rarer and found only at certain estates, among them certain classed crus. It matures late, which can result in undependable ripening in some years. A tannic variety that is high in acidity, fragrant and deeply pigmented, it can help reinforce the aging potential of wine (at a maximum proportion of 3–10%).