Wine vintage

Why is the harvest so important?

What does the harvest tell us about wine? We are accustomed to talking about the impact of terroir and human potential on wine quality. However, these are or may be constant factors, which are repeated each year. The terroir, and especially the strain, predetermined a certain profile of the wine. The characteristics of the climate, however, can be changing and often decide the quality or character of the grape.
We tend to think that the grape grows only in summer, but we do not forget that the vine has its natural cycle throughout the whole year and each season brings different challenges for the plant: winter, when the vine is sleeping; spring, when a new stage of growth begins; and summer when the berries mature, and the autumn when comes the time of harvest.
Take any date of the year, for example, your birthday. It’s always the same day of the same month but look at the photos from the last five years. Is it not true that sometimes you were obliged to wear lighter clothes and others to take shelter, is it? There are no two equal crops or seasons. Changes in temperature, amount of precipitation, the number of sunny and cloudy days, winds, possible frost, or snow in the foothills all determine to a large extent what kind of grapes we will obtain during the harvest.
The agronomist can plan his work according to the conditions of each season. Through pruning and irrigation, he can control in some percentage the performance and concentration of the grapes. But only up to a point. The wine professionals know and accept it: nature rules.

Parameters of the climate to consider

Of course, there are no ideal temperatures or precipitation values. Nature itself plays with the grape. In general, extremes are not healthy. Not too cold, but not so hot either. Nor a high humidity during the harvest because there is a risk that the grapes will develop fungal diseases. But an extremely dry season where grapes tend to dehydrate and lose their freshness and crunchiness also is not desired. 
For example, in the case of red wine, the objective is to obtain a perfect structure and aging potential, therefore it is required that the grape has the following parameters:
• High sugar level (which translates to alcohol level), which is the power/body of the wine and depends on the hours of light in the season.
• Acidity provides balance in a wine; that is to say, it is a parameter that depends on the wind and of a quite significant difference between the daily temperatures. Thanks to this factor the grapes can mature at their own pace. If we get a hot summer, especially with warmer nights on average, the grape ripens too fast, which will give the wine a lot of body and extraction but surely also a lower level of acidity.
• And the amount of water that the plant receives also has to be better balanced. Not too much so that the flavors of the grapes are diluted and only activates the growth of the leaves. Not so little so that the grapes suck and develop aromas too candied or even dehydrated. Balance is synonymous with good aromas and tannins.

How to know what the vintage means?

Yes, we do not normally follow weather reports and it is difficult to judge whether we are facing a better harvest than two or three years ago. But we can always read about the season in the regions or vineyards that interest us. This type of information can be found on the websites of the wineries, with tasting notes prepared by the winemakers themselves, or comments from the specialized press.
The year that appears on the label is directly related to the grape harvest. In the case of the southern hemisphere, the grapes are harvested mainly in late summer until early autumn, from February to May. The different styles of wine require different aging times in barrels and bottles, so the wine is launched on the market today may have a different harvest year. Its birth certificate is precisely the date the grape was cut from the grapevine.
The wine has its soul and every year adapts to the climatic conditions. The knowledge of the characteristics of the different seasons is very important for collectors. In some markets, these parameters mark the prices of the wines. Even for the most important brands, prices fall if conditions were not the most appropriate, and sometimes even decide not to market those more complicated crops.
The impact of the climate on the grape and the wine affects the quality of the wine. Only a Champagne or non-vintage sparkling wine, a port-style wine, or solera, where several harvests are mixed, can maintain greater control over the action of nature. In any other case, I recommend you buy the last four harvests of your favorite wine and do a vertical tasting. Only for your knowledge and pleasure.
Finally, I will tell you a secret: I admit that vertical tasting is one of my favorite activities. Discussions on vintages are marvelous, even at times much more heated than politics.