Soil Types

Soil Types of Interest to Viticulturists
Type
Description
Characteristics
Clay
Smallest and heaviest soil particle
Fertile (good water retention and
nutrient transfer)
Colder than looser-textured soils
(Slow ripening)
Higher acid, more tannic wines
Red wine grapes benefit from substantial 
amount of clay in soil
- Particle size allows better nutrient and 
water uptake by tiny rootlets
- Helps grape skins develop polyphenolic compounds
Merlot and Chardonnay flourish
Silt
Next largest particle
Accelerated ripening due to hydric
stress
Warmer; reflects more of sun's
rays
Loess
Mixture of clay and silt
Found in Germany and Austria
Sand
Largest-sized particle
Most loosely textured soil
Holds least amount of water
Too dry to produce high-quality
grapes
Accelerated ripening due to hydric
stress
Warmer; reflects more of sun's rays
Sandstone
Rock composed of bonded sand
Variable in density
Quality wines if containing feldspar
(Called Macigno in Chianti Classico)
Erosion turns it into sand

Loam
Combination of clay, silt, and sand
Fertile
Rich in organic matter and nutrients
Good water retention
Vigorous, thus lowering quality
Gravel
Composed of quartz
Drains freely
Excellent heat retention
Useful for late ripeners like Cabernet
Limestone
Composed of marine fossils
High in calcium (Gives wine good
structure)
Can block root development
Albarese 

Hardened marlstone that approximates limestone

High calcium carbonate content
White or pastel
Calcareous
Soil with chunks of limestone
Marl
Crumbly mixture of limestone and clay
Chalk
Special type of limestone
Soft enough for roots to penetrate
Cool
Almost perfect water delivery
Alkaline soil leads to high-acidity
wines
Low-vigor environment
Granite
Igneous rock formed in earth's core
Loosely textured soil when weathered
Drains well
Low fertility
Gamay and Syrah thrive here
Schist
Igneous rock formed in earth's core
Loosely textured soil when weathered
Drains well
Low fertility
Gamay and Syrah thrive here
Crystaline structure splits easily
into layers
Fruit, floral mineral aromas

Galestro

Highly friable clay schist (better described as shale)

Shale

Layered, hardened clay
Slate
Shale subjected to heat and pressure
Good heat and moisture retention
Volcanic
Lava, pumice, tufa from volcanoes
Macigno

Rock composed of bonded sand


Has a low calcium carbonate content
Usually dark gray, brown, or reddish-brown





Source: Compiled from education.mhusa.com



Click here to see my post on the influence of soils on vine plant growth.
Click here to see my post on soils and vineyard site selection.
Click here to see my post on the soils of the Carso and Douro regions.
Click here to see my post on Kimmeridgian soil
Click here to see my post on the soils of Champagne
Click here to see my post on the soils of the Beaujolais and Douro regions
Click here to see my post on the soils of Burgundy
Click here to see my post on the soils of the Loire Valley
Click here to see my post on the Rhone Valley soils
Click here to see my post on the soils of the Northern Rhone
Click here to see my post on the soils of Limoux AOC
Click here to see my post on the soils of Tavel AOC
Click here to see my post on the soils of Sicily
Click here to see my post on the soils of Mt Etna
Click here to see my post on the soils of Umbria and Orvieto