The Land as a Legacy

The name “Cos” may be derived from the Gascon word for “hill of pebbles” but what about the soils and subsoils that compose the hill of Cos? What is their impact on the vines that take root within? These are among the questions that drove Cos d’Estournel to pursue an in-depth analysis of its soils and subsoils nearly two decades ago. It was a long-term initiative, born of the desire to ensure that each vine plant and grape variety perfectly matched the soil in which they were planted, the ultimate goal being to preserve and pass on this invaluable legacy to future generations.

All in all, twenty soil types were identified. At the top of the hill is a gravel plateau, which lies upon a layer of gravel mixed with clay, beneath which lies a layer of very pure clay, followed by a layer of marlstone sitting upon limestone basement rock. These precise, scientific terms reflect the diversity of the estate’s subsoils. And it is the awareness of this diversity—a single plot may include two or three different types of soil—that allows Cos d’Estournel to adapt its winegrowing techniques according to the specific characteristics of subplots. As they take root in soils ranging from gravel to clay-limestone, the estate’s vines may fully benefit from an astounding complexity of terroir.

The long roots of the estate’s oldest vines give them a particular advantage: they draw upon the complexity of the deeper layers of soil while also benefitting from the specific nature of the upper layers, especially in terms of drainage. The vines of Cos d’Estournel are fifty-five years old on average but many are as old as eighty to one hundred years in age. Deeply rooted in soils that provide the nourishment they need, they draw upon the estate’s long legacy, as if able to interpret the terroir in which they grow and adapt themselves to a diversity of soils and climate—even in extreme weather conditions—to thrive and deliver a highly singular form of expression from one year to the next.

It is this very diversity and complexity that are at the heart of the grands vins of Cos d’Estournel. To ensure continuity and endow younger vines with the carefully honed wisdom of their older counterparts, the estate uses massal selection. When it comes time to replace certain vine plants, the teams prepares grafts cut from vine shoots on older vines in lieu of planting specimens cultivated elsewhere. By selecting grafts among the best and oldest vines of the estate, Cos d’Estournel perpetuates an ancestral tradition of selective breeding and ensures that the invaluable quality of its vine plants are maintained from one generation to the next.