by Karl Bradley
This week we are looking at the many types of soils that grape vines grow in and produce great grapes, as well at the parts of the world they are found.
Below are the most popular types of soil for wine growing regions.
Alluvial – This soil is a mix of sand, silt, gravel and clay that forms from mineral deposits left by running water.
Calcareous – Primarily composed of calcium carbonate and is also high in limestone or chalk as well as fossilized shells.
Sandstone – A soil with a mix of sand and silica compacted together by time and pressure.
Limestone or Chalk – Fossilized seashells that make a soft soil.
Granite – Hard, granular rock with a high level of quartz crystals.
Jory – This soil is composed of volcanic basalt, which is a dense, hard soil that has a glassy appearance.
Loam – A crumbly mix of sand, clay and silt.
Marl – A crumbly mixture of different clays as well as magnesium and calcium carbonates with fossilized shells mixed in.
Shale – Clay-like layers with fine-grained sedimentary rock that often breaks and forms beds of sharp fragments.
Tufa – A soil with a mix of calcium carbonate and silica and sometimes some volcanic ash.
Schist – A metamorphic rock derived mostly from clay, but sometimes from other rocks as well. This soft rock can flake and break easily.
Now we will look at some of the most highly regarded regions for wine based on the soil types throughout the world.
Burgundy, Champagne and the Loire Valley in France have a base of limestone marl that is rich with nutrients from fossilized shellfish. This soil produces the best Chardonnay and Pinot Noir known.
The steep slopes of Mosel produce the best Riesling in the world. The soil here is slate soil and warms quickly in the day and holds the heat into the cool evenings.
In Bordeaux, with the right bank being dominated by clay soils and the rocky gravel soils in the Haut-Médoc, this area boasts some of the most sought after wines in the world.
In Rutherford, there is a great mix of different alluvial soil types. These types range from gravelly to sandy to loamy and produce some of the most desired Cabernets from California across the world.
In Alsace, there are a variety of distinct soils throughout the region. From sandstone to granite to limestone to volcanic soils compounds, the area is known for many great Rieslings and Gewürztraminer and many others.
These are just a few of the best examples of where soil plays an important role in great wines!