Cabernet Sauvignon — Viticulture
Cabernet Sauvignon is capable of growing under various climate conditions; however, its potential as a varietal wine or blend ingredient is significantly affected by the warmth of the climate. It is one of the last important grape varieties to sprout and mature, and its growth period usually begins one or two weeks after Cabernet Franc and Merlot. The harvest period also depends on the time of the growing season.
Several wine regions in California receive abundant sunlight, but this can result in incomplete maturation, increasing the chances of varietal cabernet wines being made from the grapes. On the other hand, Bordeaux faces unpredictable weather during the harvest season, which requires cabernet sauvignon to be harvested prematurely, which is then mixed with other grapes to compensate for the deficit. In addition, some regions give priority to climate over soil conditions.
In colder regions, grapes have the potential to produce herbal and green pepper flavors, which can be unexpected considering their level of maturity. Conversely, in regions where grapes are exposed to excessive heat and overmaturation, the resulting wine may have flavors that are reminiscent of cooked or stewed blackcurrants. It is important to consider the impact of climate on grape flavor when producing wine.
New World wine producers believe that Cabernet adapts to a wide range of vineyard soils and is therefore not influenced by soil type. On the other hand, the terroir has played an important role in determining the cultivation of crucial grapes in Bordeaux. Merlot was preferred in the clay and calcareous soils of the “right bank” of Gironde, while Cabernet Sauvignon proved to be the most suitable for the gravel soils of the Médoc region, on the “left bank”. Gravel soils have the advantage of draining well and absorbing solar radiation, which favors the growth of vines.
The temperature of clay and calcareous soils is usually lower, which slows down the maturation process of the vines. In warmer regions, less fertile soils are preferred, as they reduce the vigour of the vine and result in lower yields. The American Viticultural Areas (AVA) of Oakville and Rutherford, in the Napa Valley, have dusty, alluvial soils known for giving Rutherford Cabernet Sauvignon a unique flavor called “Rutherford powder”.
Cabernet Sauvignon grown in the “terra rosa” soil region of Coonawarra (South Australia) has produced mixed results, which has caused some debate among cabernet sauvignon winegrowers in the region, since reddish soils are considered a new area for growing vines. No information has been omitted in the paraphrased text.
Apart from the degree of maturity, wine production can also be affected by crop performance, which can significantly influence the quality and flavor of the wine. The vine has the potential to produce abundant yields, especially when planted on the SO4 rhizome, known for its vigour. However, excessive production can result in wines with herbaceous or greener flavors.
In the 1970s, a new virus-free variety of Cabernet Sauvignon was developed that is known to produce high yields. This led many vineyard owners to replace their existing vines with multiple clones in the latter part of the 20th century. To reduce yields, winegrowers could choose to plant on more robust rootstocks and apply intensive pruning techniques, including cutting bunches shortly after planting to create a “green crop”.
In general, Cabernet Sauvignon is resistant to many grape diseases, but it is vulnerable to eutypella scoparia and excoriosis. However, powdery mildew is a notable exception to which it is not resistant.