Better Soil. Better Plants. Better Planet.


Specific Info - Vineyards


The word clay is often used to denote a particularly fine grain size in soils. But it is also the name of a group of flaky silicate minerals that are especially varied and complex, and crucial in vineyard soils. In line with the grain-size usage, individual flakes of clay minerals are very tiny, .002 millimetre (two thousandths of a millimetre) at most, which means we cannot discern them by eye. And it is why clays can choke the pores in the soil and curb drainage. Moreover, some clay minerals expand when wet, adding to the clogging effect but also offering water storage capabilities. In other words, clays are fundamental to the drainage behaviour of vineyard soils.

But also, each tiny clay flake presents an enormous surface area for its size. And because of the way the mineral is constructed the clay surfaces are commonly very reactive. This is the basis (together with humus) of the muchmentioned cation exchange capacity (CEC), in other words, the fertility of a soil (or lack of it, if clays are sparse). Many vineyards soils are famously barren-looking and do not have much in the way of humus, so their fertility - and all that means for vine growth and grape production - is very largely governed by the CEC of the sparse clay minerals in the soil.

The clay mineral with the highest CEC and greatest propensity to affect soil drainage is montmorillonite, named for the town in western France. When swollen with water it makes soils “thicker” or “heavier”. Some writers maintain that such soils lead to fuller, heavier wines. Most montmorillonite originates from the weathering of igneous rocks such as basalt, and related volcanic deposits. For example, the young volcanic rocks of the Tokaj-Hegyalja region, Hungary, are currently weathering into montmorillonite minerals, which, in addition to helping from some of the best vineyard sites, are being quarried for their industrial value.

Pinot Noir

Except in Champagne, Pinot Noir is not blended with other grapes. As a component in that blend, it contributes body, texture and aroma. On its own, Pinot Noir is a supple, silkywine that is relatively light in color. It is often called the most sensuous of wines. In New World versions, rich fruit dominates compared with Burgundy’s more austere, subtle elegance.

GROWING CONDITIONS Pinot Noir is genetically highly unstable, and has mutated to more than 1,000 clones in Burgundy alone. It is susceptible to heat damage as well as to frost, humidity and rot. Difficult and fragile, Pinot buds and ripens early, requiring a cool climate in order to hang on the vine long enough to develop flavor, aroma and complexity. It is moderately vigorous and low in productivity. The best soil profile for Pinot Noir is well drained, chalky clay, but it also does well in marly loam. There is a mineral in Burgundy called

MONTMORILLONITE CLAY that facilitates the plant’s absorption of elements from the soil. This may be one of the reasons red Burgundies so precisely reflect their terroir. The vine bears small, compact clusters of thin skinned berries that are high in acid, moderate in tannin and color and delicately scented.

ORIGIN AND HISTORY Pinot Noir was found in Burgundy when the Romans invaded Gaul and was among the first vines to be domesticated. The name Pinot, which comes from its pinecone shaped clusters, dates to the fourth century. Its prominence as the grape of the Côte d’Or dates to 1395, when plantings of Gamay were banned in favor of Pinot Noir. The red wines of Burgundy are among the costliest and most sought after Pinot Noirs in the world. An original Pinot prototype and an obscure vine called Gouais Blanc are the parents of Pinot Noir and 15 other French varieties, including Chardonnay and Gamay Noir. Pinot Noir has migrated from France to cool climates around the world, including California, New Zealand and Patagonia in Argentina.


Site, soil and vintages: An advanced research study was able to ascertain that at this spot, the soil is composed of a very thin clay called "montmorillonite", that cannot be found on any other land under the label of Pomerol. Petrus is probably one of the best wines in the world thanks to that clay. The nectar's color is dark, nearly black. And one must resist the temptation and let it mature many long years, so that one day, one can taste this unforgettable pleasure. Nearly 12 ha grapewine and unique soil to produce some anthology vintages : 1947, 1950, 1961, and 1990.

“Wonder Soil” Discovered!

(Paso Robles, CA) – June 5, 2011... The Discovery of a “Wonder Soil” Incomparable for Growing Premium Wine Grapes. In the latest university studies centered on Carmody McKnight Estate Vineyards & Winery (a series of seminal research projects which Cal Poly State University, SLO, in conjunction with other institutions including John Deere & Co. and the SoilTopo, LLC, launched 17 years ago) a stunning discovery has occurred – the discovery of a new “wonder soil” found nowhere else on the planet. Over 25,000 USDA soil series reviews were conducted and not one single match was found. The soil is yet to be named, but it is indeed wondrous with attributes unparalleled for the highest quality wine grape growing. The discovery happened on long-studied, leading-edge vineyards located in the Paso Robles Appellation. The pioneering proprietors are Gary Conway, Marian McKnight, Kathleen Conway and the project vineyardist/winemaker is Greg Cropper.

This “wonder soil” classifies into the “smectite” mineralogy class by the USDA soil taxonomy. The predominate clay particles are calcium montmorillonite. It is rare to find any similar soil, which is this shallow in relation to the weathered igneous (volcanic) bedrock. This revelation occurred during the most recent Cal Poly, SLO soil mapping project, conducted on Carmody McKnight Estate Vineyards & Winery and led by Thomas J. Rice, Ph.D., C.P.S.S. It ultimately required comparing this unique soil with over 25,000 USDA soil series worldwide and no comparable soil was found!

This “wonder soil” for wine grapes possesses an extraordinary balance of macronutrient (Ca, Mg, P, S, N and K) and micronutrient (Fe, Mn, Cu, etc.) contents. Significantly, the soil is notable for its extremely high cation exchange capacity (CEC), virtually a sponge for nutrients and water. The very high CEC results from the favorably elevated organic matter and smectite levels in this soil. The CEC complex in the soil retains a wide array of cationic nutrients (Ca, Mg, K, etc.), which support healthy, nutrient-rich grapes producing the most flavorfully profound and complex wines, naturally derived. "Corn flakes-looking" particles -- smectite (montmorillonite) clay minerals, magnified over 1,000 times by a scanning electron microscope (SEM)

This newly discovered soil highlights montmorillonite’s character as a powerful adsorptive for heavy metals, toxins, and other hazardous chemicals. The antibacterial effects are also well established. In addition to being a plant nutrient reservoir, the soil provides a protective detoxifying environment for grape vines.


(VITACEAE) (Frank G., Delano, CA) indicates that he applied Montmorillonite @1000 lbs per acre to ten acres of his vineyard. The foliage grew out better with a healthier color, and the fruit cane experienced a 50% gain over the non- treated vines. Some Alicante vines suffering from Pierce Disease were treated with 20 lbs each of Montmorillonite about 8-10 inches deep, and within just two weeks new growth was observed. A neighbor applied the same treatment to his diseased White Malagas and Emperor Vines with the same results.

(Pete P., Delano, CA) tells that some of his grape vines on his ranch were dying and Montmorillonite restored their vitality allowing them to bear an increased quantity of grapes of larger than usual size. Also, the grapes from the revived vines had more sugar content than those not treated. He noticed immediately the increase in moisture content of the soil.

Montirius Domain » Our soils

Our soils The greatest lands in the world only give of their best if their soil is alive! For Claude Bourguignon, agronomist in soil microbiology, ‘Red wines are as strong and complex as the internal clay surfaces supporting them are of high density’ What is the internal surface of clay? Clay is composed of layered sheets. Side by side, these sheets represent the surface of clay. The internal surface is the sum of the surface of these layers per 1 gram of clay. The higher the internal surface area, the higher the quality and complexity of the clay. The quality of the clay is measured by square meter of the internal surface per gram of clay.

Our soils are very clay rich. They are mostly composed of: Garrigue or plane soil which is ‘Mindel’ clayey limestone on the surface containing ‘ICTITES’ clay.

‘Pliocene’ clayey blue marl containing ‘SMECTITES’ clay. ‘

Helvetian’ sand and sandstone containing 'MONTMORILLONITE ’ clay This is soil which is found in the Chateauneuf du Pape, Gigondas and Vacqueyras classifications. sol-coupegarrigues Garrigues soil

Our estate is essentially situated on Garrigues soil : Earth + pebbles on 1 to 2 meters depth (photo). These are ancient MINDEL alluvial deposits (claylimestone formation). The internal surface of these clays are contained between 200 and 250 square meter per gram. The dark color of the soil and the pebbles accumulates heat which favours the grapes maturity. sol-coucheargile.

Blue clay Marns Under the Garrigue soil (between two and fifteen meters deep) are situated the blue clay Marns of the PLIOCENE. The internal surface is about 300 square meter per gram. The blue clay marns don’t exist on the ” clos ” plot. The photo shows the different colors of the Garrigue (dark) and the blue clay Marns (pale).

terroir_rocher_sable Sand and sandstone (MONTMORILLONITE) Under these blue clay Marns, appears the base on which lays our soil : yellow sand and sandstone of the HELVETIAN period. Helvetian sand and sandstone have an internal surface of 600 square meter per gram called Montmorillonite. MONTMORILLONITE is the best clay to produce reds wines of high quality.