Role of Terroir in Grape Growing
The natural environment of a specific region offers a complex interaction of climate, microclimate, soil composition and character, drainage, sunlight exposure, and elevation which all contribute to the unique character of wines from a specific locality. The sum of these factors are called Terroir.
In order to make good wines, grapes should be grown in moderate, temperate climates. Winters must be mild enough to avoid damaging grapes, and summers must be warm enough in order to ripen them sufficiently. At the same time, if summers are too hot grapes will over ripen as well as be unable to retain their acidity. The terroir of a piece of land encompasses these factors.
Therefore, wine growing regions are restricted to a narrow range of mean temperatures (approximately 50 degrees Fahrenheit average annual temperature), generally found between 30 and 50 degrees latitude, often in areas near the coast.