Climate conditions vary considerably across the area of production of Grana Padano PDO. Although the climate in the Region of Lombardy can be broadly defined as semi-continental, it is very diverse due to variations in the physical characteristics of the territory, which includes mountains, hills, lakes and plains. On the plains, the climate is typically continental, with cold winters characterised by frequent frost and thick fog, and hot, humid and sultry summers with moderate rainfall. In the summer, temperatures reach above 30°C and humidity can exceed 90%. The Po Valley is one of the least windy regions in the world. The areas around the great Italian lakes, by contrast, have a mild, more Mediterranean than continental climate, in which the winters are not as cold and the summers are hot but breezy. The climate in Trentino can be described as one of transition between a semi-continental and an Alpine climate. Although the average altitude of most of the region’s territory is rather high, it does not suffer from the harsh winters typically affecting other Alpine areas. Due to the total absence of fog and low humidity levels, it enjoys an essentially dry climate. The climate in Emilia Romagna, although predominantly subcontinental, also varies significantly. The region has moderate winds and the prevailing westerly winds create the right conditions for brief periods of relatively mild weather. The rainfall is mostly concentrated in the spring and autumn, and its levels are lower than in the regions north of the Po River. Two types of climate coexist in this region, which can be divided into plains and mountain climate, the former with continental characteristics and the latter with all the typical weather conditions of the Apennines. The region of Veneto has similarly varied climate conditions. Here, mountainous areas with harsh winters, in which temperatures drop well below zero, alternate with foothill areas that enjoy a more temperate climate, being exposed to the south and sheltered to the north by the Alpine foothills. The climate on the Veneto plains, albeit milder than in other areas of the Po Valley, is marginally influenced by the mitigating effect of the Adriatic Sea. A major feature of the entire region is the considerable drop in night time temperatures. In Piedmont, particularly in the province of Cuneo, the climate has strongly continental characteristics due to the barrier effect created by the high hills against the influence of the Mediterranean Sea, despite its proximity. The different altitudes within the province lead to considerable climate differences between the Alpine area, the Langhe hills and the plains.

The climate across the territory is clearly highly diverse and this, alongside the physical features of the land, influences significantly the type of forage crops used to feed the dairy cows that produce the milk from which Grana Padano PDO is made.
The different contents and nutrients of their diet determine the colour, aroma, structure and flavour of the cheese and whether or not it is suitable for long ageing periods.
The provinces of Brescia, Bergamo and Cremona have a strong tradition of corn production and a lot less land is allocated to pastures and meadows than in other provinces. As a result, the Grana Padano PDO produced in these areas has a more delicate flavour and a less intense aroma. The colour of the cheese is also less intense and the ageing period is shorter.
By contrast, in the provinces of Mantua and Piacenza the emphasis is predominantly on forage crops grown on pasture lands and meadows, both permanent and temporary, resulting in a cheese with a stronger aroma, a more intense flavour and more suited to ageing.
The hilly areas around the provinces of Vicenza and Verona, as well as the provinces of Trento and Cuneo situated at the foothills of the Alps, are rich in hill and mountain pastures in which permanent meadows and spontaneous crop lands of grasses dominate cheese production. With this kind of cattle diet, the resulting Grana Padano PDO has richer aromas, more intense and variegated flavours and the colour of the cheese is straw yellow.

The last, but not least important factor of biodiversity has to do with the different breeds of dairy cows that produce the milk for Grana Padano PDO.
The two breeds used are the Italian Friesian and Alpine Brown, which for many decades have represented the animal husbandry tradition in the area of production of Grana Padano PDO.

The Alpine Brown
The Alpine Brown is the Italian strain of the Brown breed from central Switzerland, improved with new blood from the American Brown Swiss breed. The introduction of the Alpine Brown in Italy dates back to the 16th century, but it was not until 1850 that the breed became widely established, starting from the southern valleys of the Alps and gradually spreading to the Po Valley. In the large dairy farms of Lombardy, where dairy cattle farming was already well-established, the Alpine Brown gradually replaced local cattle breeds and within a century it became Italy’s most important dairy cow, with almost 2 million heads of cattle. This breed still stands out today for its robust constitution, adaptability to harsh climates, longevity and large as well as constant production of fat- and protein-rich milk.

The Italian Friesian
The Friesian cattle breed farmed in Italy represents the Italian “strain” of the black pied or Friesian cow, originating from the Dutch Friesian after which it is named, and is the result of the introduction of Canadian and North American blood into the stock. The first significant imports of the breed were in 1920, but its widespread introduction in large-scale forage areas like the Po Valley took place especially after World War Two. Due to its highly cosmopolitan characteristics, wherever the breed has been farmed it has developed peculiar features associated with the particular environmental conditions of the local area. Thanks to its high dairy yield, strong constitution and early milk production and development age, it has eventually come to replace many local, less productive, breeds.