Definition - What does Limestone mean?
Limestone is present in vineyard soils all over the globe, contributing to the unique characteristics of many great wines. Limestone is a porous sedimentary rock made from calcite and aragonite minerals usually left over in soils from prehistoric marine skeletons. In vineyards, limestone present in soils can help with retaining water and proper drainage as well as contributing nutrients that make sweeter, superior grapes. It makes most commonly distinguished Cabernet Sauvignon, Pinot Noir and Chardonnay wines made from grapes grown in its soils.
WineFrog explains Limestone
Some of the world’s most famous vineyards are planted on soils that contain limestone, most notably the French regions of Chablis, Champagne, Burgundy, the southern Rhone and Loire valleys, and the Bordeaux region of Saint-Emilion. There are also limestone soils in Coonwarra Australia, the Nemea region in Greece, and in some parts of California. It must be noted that limestone is just present in other soil types, as pure limestone alone is too dense for any plant roots to permeate.
The limestone that is in the soils contains calcium carbonate from the decayed marine fossils which helps the soil retain water without the soil becoming oversaturated. This natural irrigation system of limestone helps those areas that cannot be irrigated artificially. The nutrients found in calcium have less pH and are less acidic, the calcium also increases nutrient intake and both of these combine to make a higher grape acidity with a lower pH. However, too much limestone can be detrimental to plant growth, as it will increase pH levels and take away iron that plants need for photosynthesis and growth.