As students of the grape, we love to dissect every single element of a particular vintage; Palate, Aroma, Region, Appellation, Body, Finish, Acidity…the list goes on and on.
All of these factors are obviously essential in tasting notes that are thorough and comprehensive. However, I want to talk about a variable that is always mentioned, read at a glance, and without full understanding: Soil.
The mention of soil isn’t entirely shocking, or shocking at all for that matter. Soil is the very element that is present from the very inception of the grape. Not to wax poetic, but the wine we drink is literally born from the soil in which it grows…
Okay, let’s dig in the dirt!
In general, most vineyard topsoil’s are not homogenous; often a blend of different soils, and both the rocks within and the texture of the topsoil influence a region’s vines. Soils help regulate climate fluctuations, retain heat, and can even help in dispersing water.
Depth and composition of a soil (nutrients, drainage, water retention, pH) all have their effects on the wines we drink.
- Wine Vocab: “Minerality” — the perceived aroma and flavor of a soil in the wine itself
- Fun Fact: There is no scientific evidence that proves that grapevines can extract chemical compounds directly from the soils!
While certain soil characteristics are suited to different regions, generally vineyard soils should not be too fertile. The general ‘rule of thumb’ is that truly good wine soils should retain water, while still draining it away from the surface.
Buckle up, We’ve got a lot of ground to cover!
(14 different types of ground to be specific)
Made From The Cooling And Solidification Of Magma/Lava
We start this party off with a BOOM!
Volcanic soil is 1 of the 2 Igneous soil types. Volcanic Soil starts out as Basalt rock.
It’s fined grained, holds water but also drains well, retains heat as well as reflecting it!
Famous Regions- Sicily, Canary Islands, Soave, Santorini
The Hard Truth
Granite forms under the Earth’s crust and mixes with Magma and Quartz. If the Ph in the soil is elevated, there will be higher acidity in the soil.
This soil is porous which solid for deep-rooted vines.
Famous Regions: Cornas, Rais Baixas
Much like a caterpillar transforming into a beautiful butterfly, these soils have also transformed from another type of rock through heat and pressure over millions of years!
Pronounced like “Nice, France” which is spelled the same way as “Nice”
as in “good”…sadly this soil is not…
Since the mineral composition of Gneiss is often similar to granite and weathering rates are slow, gneiss tends to lead to acidic, poorly developed soils.
Famous* Regions: Wachau and Kamptal
*we’re using this word loosely in this case
The gist of Schist
Schist is a hard, crystalline rock which is denser than slate. It has layers of minerals that can flake off easily and also retains heat well.
This soil produces BIG powerful wines with rich minerality.
Famous Regions: Douro Valley, Ribeira Sacra
Slate begins its’ journey as a deposit subjected to great pressure and heat. It is chemically unmotivated and impervious to weathering.
Delicate grapes valued for pure varietal characteristics and that are made in stainless steel tanks are grown in these soils.
Famous Region: Mosel
Comprised Of Solidified Mineral Or Organic Deposits From The Earth,
Often Left By Bodies Of Water
Life is a beach and I’m just playin’ in the
Sandstone is comprised of sedimentary rock, sand-sized particles that have been compacted together over time by pressure and it can be comprised of different rock and create assorted colors.
Famous Wine Regions: Chianti Classico
Living Up To The Namesake
Limestone is exalted as one of the best soils for wine production. It is formed from decomposed bodies of organic material in ancient sea beds and reefs aka fossilized sea shells. The soil drains well but also holds water for vines to absorb when needed.
Wines grown in Limestone soil tend to be long-lived and have bright, linear acidity.
Famous Wine Regions: Burgundy, Champagne
Heavy Metal, Hard Rock
Flint/Silex is hard and metal-like and formed from Silicon Dioxide. This soil stores and reflects heat and provides a great environment for ripening, especially in areas typically too cold for grape growing.
These elements give wine a rich, flinty minerality.
Famous Wine Regions: Sancerre, Pouilly Fume
The “Big 6” Soil Textures
A True Amalgamation
Alluvium is blend of soils typically clay, silt, sand, and gravel. It is deposited by many years of running water usually contains a lot of organic material, making it more fertile.
Alluvial soils are present in many wine regions around the world.
Famous Wine Regions: Napa Valley Floor
Messiah Of Parched Vines
Clay soil retains precipitation and minerals and the savior to vines in dry times. It also helps vines stay cooler in warmer growing regions (think Spain) and imparts flavors intuitive to clay itself—thick, round, and generous.
These wines are Muscular with high extract and color
Famous Wine Regions: Pomerol, Rioja, Ribeira Del Duero
My Soil Is Big and Boozy
Gravel soil has a wide range in size (pebble to fist size) which is helpful in absorbing heat to reflect back to grapes.
These factors allow the region to make wines bigger and more alcoholic than they typically would be able to in that climate.
Famous Wine Regions: Left Bank Bordeaux, Châteauneuf du Pape
The fairest soil in all the land
Sand is any rock that has been pulverized into small particles. It also works well with wet climates and drains easily. In warm climate regions, sandy soils make wines that are ‘softer’ with less color, lighter acidity and tannin.
In cooler climate regions, sandy soils benefit vineyards by retaining heat and draining well to produce highly aromatic wines
Sandy soil produces Elegant wines with high aromatics, pale color and low tannin-trés chic indeed!
Famous wine regions: Barolo, Swartland (South Africa), Graves
Change the “l” to an “h” and put it after the “s”;
that sums up your chances for planting roots
Silt soils are more finely textured than sand; think ultra-pulverized glitter minus the sparkle. This soil retains much water and usually has some limestone mixed in.
Silt soil is so fine that it makes growing anything, much less grapes, VERY challenging.
These wines are smooth and round wines with slightly less acidity.
Famous Wine Regions: Neiderosterreich, Austria, for Gruner Veltliner, Washington State
Think the “Aphrodite” of Soils
Loam soils are a warm, soft, crumbly mix of sand, silt, and clay.
These soils can be too fertile for good wine, but when in right combo of soil textures, can make powerful, voluptuous wines.
Loamy wines are gifted with a pleasant, sweet, earthy aroma. Some say that those with the flair of a “green thumb” truly appreciate these notes because they are synonymous with gardening.
Famous Wine Regions: Barossa Valley
Well there you have it! All (14) soil types that are imperative to your understanding of where the wine you drink came from. I am certain that this information will provide endless witty anecdotes and great stories to tell at parties! Well maybe not all of that, but you can at least school the pretentious boob who is claiming “Gneiss soil lacks acidity and produces excellent wine”! Pssht.