Viticulture (soil types, growing environment)

Question 1

What are the four primary soil types?

Answer 1

1. Sandy Soils
2. Clay Based Soils
3. Silt Soils
4. Loam Soils

Question 2

The properties of sandy soils and best wines from them

Answer 2

• Sandy soils are well-drained and retain heat.
• In cool climate produce highly aromatic wines.
• In warm climate make ‘softer’ wines with less color, lighter acidity and tannin. eg Swartland, South Africa
• resist pests (esp phyllox) encourages organic
• Barolo Cannubi sandy clay soils - intense aromatics, light tannin and very pale color.
• Northern Médoc (close to the sea), Graves. Lighter, more aromatic Cabernet Sauvignon.
• In Lodi 1890’s Zinfandel survived phylloxera

Question 3

The properties of clay soils and best wines from them

Answer 3

• Clay soils stay cooler and retain water.
• several types, including a lime rich clay called Calcareous Clay - even cooler. Make boldest red and white wines
• In Rioja and Ribera del Duero, best Tempranillo vineyards grow on limestone-rich clay soils.
• Vosne-Romanée best Pinot on Marl - clay limestone soil
• In Chianti Sangiovese on Albarese soil is a clay-limestone
• Napa hillside vineyards on clay loam
• great Barossa Shiraz on clay-loam soils

Question 4

The properties of silt soils (eg loess) and best wines from them

Answer 4

• Smooth and round wines with slightly less acidity
• silt soils retain water and heat
• very fine grained - growing roots very difficult
• In cooler climate regions that have sun, the ideal silt soil sites tend to be mixed with a portion of limestone
• Loess (wind-blown silt) soils in eastern Washington covers the sandy-loam ancient flood soils below. Wines are highly aromatic, lighter color and smooth tannin.
• Oregon Pinot Noir often on loess/ silt- clay.

Question 5

The properties of loam soils and best wines from them

Answer 5

• Loam is too fertile unless it’s blended
• a mix of silt, clay and sand as well as an organic matter called humus
• very fertile, causes vineyards to be over vigorous = wines with little flavor and color. Yet offer great potential if rigorous pruning regimes
• parts of Sonoma Valley and Napa Valley is sandy-loam - the sand keeps soil poor enough for high quality grapes

Question 6

the effects of gravel, slate, schist and volcanic soils

Answer 6

• gravel, slate, schist are rocks which can change the temperature of a soil (by retaining heat or reflecting sun) and they also affect drainage.
• in Bordeaux the gravel in the clay soil increases drainage
• in cool Mosel Valley blue slate retains heat from the sun
• decomposed volcanic soils retain water - good in dry regions eg Lanzarote (Spain), Santorini

Question 7

Limestone rich soils and great wine

Answer 7

• limestone gives nutrients to vines - to grow better/ produce sweeter grapes.
• retains moisture in dry weather, good drainage in wet
• one negative of lime is it causes iron deficiency in grapes so high lime content soils must be fertilized frequently
• Great whites: chalk soils of Aube in Champagne; Chablis in Burgundy; Pouilly/Sancerre in Loire Valley produce bold-flavored zesty white wines.
• Calcareous soils in Southern Rhône famous for classic Côtes du Rhône of Grenache, Syrah and Mourvèdre
• similar soils for same grapes in Paso Robles, California

Question 8

all the areas to consider in growing environment

Answer 8

• temperature, sunlight, latitude
• altitude, slopes, aspects, proximity to water
• winds
• soil characteristics, nutrients
• mist, fog, clouds
• diurnal range
• rainfall
• climate (growing days)
• weather, El Nino, La Nina
• climate change