Where does wine grow?
In order to develop high-quality and ripe grapes, the vine needs above all warmth and light. Both are provided by the sun, so a south-facing slope is ideal for a vineyard. On slopes, thermals are also favourable: cold air currents fall down the slope at night and warm air currents rise during the day. Water bodies (rivers, lakes, seas) also have a positive effect because they reflect the sunlight.
The optimal temperature for grape growth is between 25 and 28 degrees Celsius. The temperature depends largely on the altitude at which the vines are planted; as a rule of thumb, the temperature drops by 0.6 degrees for every 100 metres of altitude difference upwards.
The minimum requirements for viticulture are an average annual temperature of at least 9 degrees Celsius, an average temperature of the warmest month of at least 18 degrees Celsius, a maximum low temperature in winter of minus 13 degrees Celsius, at least 1,300 hours of sunshine per year, an annual precipitation of at least 500 mm (in warm climates at least 750 mm) and a growing season (the time between the last frost and the first frost) of at least 180 days.
Against this background, viticulture is only possible in certain areas of the earth, the so-called vine belts. These extend roughly between the 40th and 50th degrees of latitude in the northern hemisphere and between the 30th and 40th degrees of latitude in the southern hemisphere. Central and southern Europe, the USA, Chile, Argentina, South Africa, South Australia and New Zealand, for example, are located in these zones, where a temperate climate prevails. Whether a region is climatically suitable for the cultivation of vines is determined by its viticultural suitability, which is scientifically investigated and determined.