Bordeaux Climate, Terroir, and Main Grape Varieties
Climate and Terroir
Bordeaux wine region is located in the Eastern portion of France. It extends north, south and west of Bordeaux City. The Garonne River and Dordogne River meet at the Gironde Estuary which flows from the Atlantic Ocean. The area to the East of the Gironde Estuary and the Garonne River is identified as the Left bank. The area to the west of the Dordogne is considered the Right Bank. In between the Garonne River and the Dordogne River is considered Entre-Deux-Mers.
The climate of Bordeaux is a maritime warm climate. It is moderated by the warm Gulf Stream Currents. Sand Dunes and the Landes Forest protect the region from the gusty winds of the Atlantic Ocean. Humidity and significant rainfall occur throughout the year. The rainfall can disrupt flowering, fruit set, and dilute the flavors at harvest. For this reason, there can be variation of grape quality from year to year. Blends are one way the winemakers have adapted to the effects from the weather. In the southern region near Graves and Sauternes, the Ciron River brings in humidity and fog which develops Botrytis on the Sémillon grapes for sweet wine production.
Main Grape Varieties
The different grape varieties are specifically selected to grow in Bordeaux. They begin their growth and ripen at different times. This allows the weather to not significantly impact the quality of all grapes at harvest. The main black grape varieties grown in Bordeaux are Cabernet Sauvignon, Cabernet Franc, Merlot, and Petit Verdot. The main white grapes produced in Bordeaux are Sauvignon Blanc, Sémillon, and Muscadelle.
Cabernet Sauvignon is predominantly grown on the Left Bank. The gravelly soil provides reflective heat and drainage that allows the Cabernet Sauvignon to fully ripen. Cabernet Sauvignon adds strong tannins and black currant fruit flavors to blends, and it has potential for aging. Premium Cabernet Sauvignon are grown in Médoc, Haut Médoc, Margaux and Pessac-Leognan.
Merlot is grown widespread across the region of Bordeaux, but it is predominantly grown in the cooler clay soil of the Right Bank. It is early ripening, and it adds a richer body to blends. Premium Merlot grapes are grown in St. Émilion and Pomerol.
Cabernet Franc and Petit Verdot are grown in smaller quantities. Cabernet Franc when it is less ripe will have herbaceous flavor, but when it is ripe will add black fruit and floral notes. Petite Verdot adds strong color and tannins to wine.
The three main white varieties are Sémillon, Sauvignon Blanc, and Muscadelle. These grapes all play a part in dry and sweet white blends. Whites are grown in the southern portion of Bordeaux and are approved for areas such as Pessac-Leognan, Graves, and Entre-Deux Mers. Sémillon is affected by botrytis which is an important component in sweet wine production. Sauvignon Blanc is the leading grape for dry white blends with Sémillon as the secondary grape.
