One of the most important factors that determine the quality of wine is the type of soil in which the grapes are grown. While there are many different soil types that can influence the character of wine, limestone soils are widely regarded as some of the most desirable for grape cultivation.
This summer, I visited Jan Raumland at Sekthaus Raumland to delve deeper into the intricacies of limestone and its impact on both the grapevine and the resulting wine.
Max Kaindl, 18. August 2023
updated: 09. December 2023
Reading time about 4 minutes
In July, I dropped by Sekthaus Raumland for a laid-back evening with Jan, the Raumland family and some friends of theirs. The next day, our casual plans turned into an unplanned vineyard tour. Jan guided me through the Raumland parcels, including those dedicated to his impressive new wine line, WongAmat (I must say, the debut Pinots from 2021 are truly remarkable). Throughout our tour, Jan shared numerous intriguing insights into the profound influence of the limestone-rich soil prevalent in the region. The profound influence of this specific type of soil on the grapes became a fascinating topic of discussion which inspired me to write this article. Later that day, wine critic Stephan Reinhardt joined us on our vineyard tour, making the visit even more memorable.
But now, let’s shift away from my anecdotes about wine-soaked summer evenings and vineyard tours with winemakers. Here are the crucial facts about the impact of limestone on soil and wine.
These soil types are characterized by their high levels of calcium carbonate, which is derived from ancient marine organisms such as shellfish and coral. These soils are typically well-drained, with good water retention and a neutral to slightly alkaline pH. The calcium carbonate in the soil provides several benefits for grapevines, including improved water uptake and root penetration, increased nutrient availability, and improved soil structure.
Calcareous soils, inherently alkaline, excel in maintaining cool soil temperatures while efficiently storing water without causing stagnation. This combination creates an optimal environment for grapevines, delaying grape maturation and instilling a desirable acidity in the fruit.
The foundation of calcareous soils lies in limestone, a sedimentary rock formed from the accumulation of marine organisms such as shells. Gray limestone, prevalent in vineyards (except for white chalk), exhibits consistent alkalinity, making it a preferred choice for planting grape varieties boasting high acidity.
Beyond limestone, calcareous rocks encompass a spectrum of stones with varying compositions, predominantly featuring calcium carbonate. Ranging from the harder limestone to the softer chalk and crystalline marble, these rocks contribute to the unique character of calcareous soils.
Calcareous soils, widely embraced in European vineyards, offer favorable conditions for grapevine growth, particularly in cooler climates and hilly terrains. Known for their well-drained, skeleton-rich, and quick-warming attributes, these soils are associated with high-quality wine production, especially for white grape varieties.
The mineral-rich content of calcareous soils, notably rich in calcium, not only aids water drainage but also influences nutrient absorption, shaping the structure of the wine. While excessive calcium can lead to chlorosis, an insufficient amount can acidify the soil. White grape varieties, notably Chardonnay or Riesling, thrive on calcareous soils, resulting in wines with heightened acidity, distinctive minerality, and a lusciously smooth taste.
Calcareous soils emerge as versatile influencers in viticulture, imparting distinct characteristics to grapes and contributing to the overall excellence of wines. While the direct scientific links between soil types and taste are evolving, the empirical evidence from the wine industry underscores the pivotal role of calcareous soils in shaping the unique attributes of grapes and their resulting wines.
