The 'soil composition of vineyards' is one of the most important
viticultural consideration when planting grape vines. The soil supports the
root structure of the vine and influences the drainage levels and amount of
minerals and nutrients that the vine is exposed to. The ideal circumstance for a vine is an area of thin
topsoil and
subsoil that sufficiently retains waters but also has good drainage so that the vine roots don't become overly saturated. The ability of the soil to retain heat and/or reflect it back up to the vine is also an important consideration that affects the ripening of the grape.
[1]
There are several minerals that are vital to the health of vines that all good vineyard soils have. These include
calcium which helps to neutralize the
Soil pH levels,
iron which is essential for
photosynthesis,
magnesium which is an important component of
chlorophyll,
nitrogen which is assimilated in the form of
nitrates,
phosphates which encourages root development, and
potassium which improves the vine metabolisms and increases it health for next year's crop.
List of soil types
''Unless otherwise noted the primary reference for this list is Sotheby's Wine Encyclopedia 2005''
A-C
★ Albariza - Formed by
diatomaceous deposits. Found in southern
Spain
★
Alluvial soil- Highly fertile soil that has been transported by a river. Often contains
gravel,
sand and
silt.
★
Basalt-
Volcanic rock that is high in
Sodium carbonate and
limestone. Very low
quartz and
potash content.
★ Boulbènes - Fine
siliceous that is easily compressed and common in the
Entre-Deux-Mers region of
Bordeaux.
★ Calcareous soil -
Alkaline soil with high levels of
calcium and
Magnesium carbonate. Typically cool in temperature soil that provides good water retention and drainage. 'Calcareous clay' soils have high
limestone content that neutralizes natural acidity of the soil. However the cool temperatures of the soil normally delay ripening in the grape which tends to produce more acidic wines.
★ Carbonaceous soil - Soil produced through the
anaerobic decomposition of rotting vegetation. This type of soil includes
anthracite,
coal,
lignite and
peat.
★
Chalk - Very
porous soft limestone soil that vine roots can easily penetrate. It provides good drainage and works best for grapes with high acidity levels.
★
Clay -
Sedimentary rock based soil that has good water retention ability but poor drainage. The soil is often very cool and high in acidity. The Right Bank of
Bordeaux is dominated by clay based soils.
[2]
D-H
★
Dolomite - Calcium-magnesium carbonate soil.
★
Flint - Siliceous stone that reflects and retain heat well. The
Pouilly-Fumé wine of the
Loire Valley is generally produced on Flint-based soil and is said to have "gun-flint" smell in the wine.
★ Galestro -
Schist based soil found in the
Tuscany region of
Italy.
★
Granite - Composed of 40-60% quartz, 30-40%
Orthoclase and various amounts of
hornblende,
mica, and other minerals. This soil warms quickly and retains heat well. The soil's high level of acidity works to minimize the acid levels in the grapes which works well with acidic grapes like
Gamay. It is the main soil type of the Brand region of
Alsace.
★
Gravel - Loose siliceous pebble soil that has good drainage but poor fertility. Vines planted in this type of soil must penetrate deeply to try to and find nutrients in the subsoil. Wine made from vines produces on clay gravel beds have less acidity then those planted on limestone gravel beds. The
Graves region of Bordeaux and
Sauternes is dominated by gravel based soil.
★
Greywacke - Sedimentary soil formed by rivers depositing quartz,
mudstone and
feldspar. It is found in vineyards of
Germany,
New Zealand and
South Africa.
★
Gypsum - Calcium
sulfite based soil that is formed through the
evaporation of
seawater. It is a high absorbent soil that has average drainage ability.
★
Hardpan - A dense layer of clay that is impenetrable by roots and water. In some areas of
Bordeaux, a
sandy iron rich layer is located deep enough below the surface to act as a
water table for the vine.
I-Q
★
Keuper - Soil type consisting of
marl and
limestone common in
Alsace dating back from the
Upper Triassic period.
★ Kimmeridgian soil - A gray colored limestone based soil originally identified in
Kimmeridge, England. 'Kimmeridgian clay' is calcareous clay containing Kimmeridgian limestone. This is the principle soil type of the
Loire Valley,
Champagne and
Burgundy regions.
★
Lignite - soil type used as fertilizer in
Germany and
Champagne. It is a brown colored carbonaceous soil that is an intermediate between
peat and
coal.
★
Limestone - Sedimentary based soil consisting of
carbonates. The most common colored limestone found in wine producing area is buff-gray in color (with the exception of white
chalk). The water retention abilities vary from composition but limestone is consistently
alkaline and is generally planted with grapes of high acidity levels. This is the main soil type in the
Zinnkoepflé region of Alsace.
★
Llicorella - A soil type found in the
Montsant region of Spain. The soil is a mix of slate and quartz that dates back to the
Paleolithic era. The soil is very porous and drains well.
Syrah,
Grenache and
Carignan have done well in this soil type.
★
Loam - Warm, soft, fertile soil composed of roughly equal amounts of
silt,
sand and
clay. It is typically too fertile for high quality wines that need to limit yields in order to concentrate flavors.
★
Loess - A silt based soil composed of wind borne materials that are normally weathered and decalcified. The soil has good water retention and warming properties.
★
Marl - Calcerous clay based soil that is cold and adds acidity to the wine. Vine planted in this type of soil normally ripening later then in other soil types. 'Marlstone' is a limestone based clay that acts similar to Marl.
★
Mica -
Silicate based soil composed of fine, decomposed rock formations.
★
Muschelkalk -Soil type consisting of various compositions of
sandstone, marl,
dolomite, and
shingle common in Alsace dating back from the
Middle Triassic period.
★
Perlite - A
volcanic soil type that is light, powdery and lustrous in characteristic with properties similar to
diatomaceous earth.
★
Quartz - Common material found in most vineyard soils-especially sand and silt based soils. The high
Soil pH of quartz can reduce the acidity of the resulting wines but its heat retaining properties that stores and reflect heat can increase ripening of the grape which normally results in wine of higher alcohol content.
S-Z
★
Sand - warm, airy soil that is composed of tiny particles of weathered rocks. One of the few soils that the
phylloxera louse does not thrive in, the soil drain wells but does not have good water retention. 'Sandstone' is a
sedimentary soil composed of sand particles that has been pressured bound by various
iron based minerals. This is the main soil type of
Kitterlé in Alsace.
★
Schist - Laminated,
crystalline rock based soil that retains heat well and is rich in
magnesium and
potassium but is poor in organic nutrients and
nitrogens.
★
Shale - Fine grain sedimentary based soil that can turn into
slate when under pressure. The soil is moderately fertile and retains heat well.
★ Siliceous soil - Soil composed of
acid rock that are crystalline in nature. The soil has good heat retention but needs the added composition of
silt,
clay and other sedimentary soils to have any kind of water retention. The range of this soil can include organic materials like
Kieselguhr and
flint or inorganic materials like
quartz. This soil type covers half of the
wine regions of
Bordeaux.
★
Silt - Soil type consisting of fine grain deposits that offer good water retention but poor drainage. It is more fertile the sand.
★
Silex - A flint and sand based soil type found primarily in the
Loire Valley that is a formed from a mixture of clay, limestone and
silca.
★
Slate - Soil type that is the most common found in the
Mosel-Saar-Ruwer region that is a dark gray, plate like rock that formed when clay, shale,
siltstone and other sediments are subjected to pressure. The soil retains heat well and warms up relatively quickly.
★ Steige - A schist based soil found in the
Andlau region of
Alsace. In the
Alsace Grand Cru AOC of Kastelberg the soil has
metamorphosed with
granite sand to form a hard, dark slate like stone.
★
Terra Rossa - A sedimentary soil, known as "Red Earth", that is created after
carbonates have been leached out of limestone. The breakdown leaves behind iron deposits which
oxidizes and turns the soil a rustic red color. This soil type is found in some areas along the
Mediterranean and in
Coonawarra, Australia. The soil drains well and is relatively high in nutrients. Australian winemakers have found some success with
Cabernet Sauvignon plantings.
★ Volcanic soil - Soil that is created by one of two volcanic activities. 1.) ''Vent-based soil'' is material that has been ejected into the air, cooled and settled to the earth. These include
pumice and
tufa. 2.) ''Lava-based soil'' are the product of
lava flows from the volcano. 90 percent of lava-based soil is composed of
basalt with the other ten percent including
andesite,
pitchstone,
rhyolite, and
trachyte.
References
1. T. Stevenson ''"The Sotheby's Wine Encyclopedia"'' pg 16 Dorling Kindersley 2005 ISBN 0756613248
2. E. S. Brown ''"The World's Top 10 Wine Soils Wine Geeks 7/5/2007