The technical team is keen to maintain a subtle balance between working the vineyard whilst fully respecting the environment and the development of the wine based on the harmonious blending of traditions and modernity.Gruaud-Larose stands out its obvious concern to produce a wine of excellence as... naturally as possible. The team plans to obtain the ISO 14 000 certification, which would consecrate the efforts of the last decade. Over a million years ago, during the Quaternary period, a G¸nzian layer formed beneath all the grands crus classÈs of the MÈdoc and covered the Tertiary layer of chalk and clay. The geological structure of the soil at Gruaud-Larose is particularly rare consisting of a uniform layer of six metres of gravelly clay over the entire Domaine. The gravel creates acid soil, which, whilst being poor for agricultural purposes, enables good drainage, and provides excellent conditions for viticulture. In addition to the vines being encouraged to form deep roots to find water, the poor soil limits their growth and general vigour, thereby improving the concentration of sugar in the grapes. The vineyards of St. Julien benefit from an oceanic climate, which is characterised by generous rainfalls (80 to 90 centimetres) in the winter and spring that ensure growth, and then hot and dry summers and autumns that provide ideal conditions for the grapes to ripen. Chateau Gruaud-Larose Domaine stretches over 200 uninterrupted acres and consists of more than 700,000 vines. The current proportions of the different grape varieties grown are 57% Cabernet Sauvignon, 30% Merlot, 8% Cabernet Franc, 3% Petit Verdot and 2% Malbec. The quantities of each variety used in the wines vary from year to year, enabling greater complexity. Cabernet Sauvignon, the king of the MÈdoc grapes, is traditionally the main variety used in the wines of the region. Its proportion varies between 40 and 60%. Merlot has become the main grape of the Gironde, and whilst synonymous with St. Emilion and Pomerol it has remained in the minority in the MÈdoc. Although a secondary ingredient in the grand vin of Gruaud Larose, Merlot still makes an important contribution to the wineís remarkable complexity. Cabernet Franc, also known as Breton and Bouchet, is a very old French variety. Well-suited to wines that will mature over a long period, Cabernet Franc can produce fine wines of great complexity. Petit Verdot, a late maturing variety typical of the MÈdoc, is valued for its colour and high potential alcohol content. No longer grown on many estates because of its fragility, it produces excellent results at Gruaud Larose, and is an integral part of the wine. Malbec, also known as Cot, suffers from a susceptibility to coulure (a failure to set fruit) but, despite this, makes an unquestionable contribution to the wineís complexity of flavour.