The Harvest Season
The harvest season corresponds to the time of year when grapes intended for wine production are picked (this does not include table grapes). Depending on the region, it can take place between August and October.
How is the harvest date chosen?
Generally, the harvest is set about one hundred days after the first vine flower appears, which corresponds to the fruit’s maturity. Grapes are indeed picked once they have reached maturity, but this can be influenced by many factors. For example, sun exposure, grape variety, or altitude.
Note that there are several types of maturity to consider. So, a date must be found that roughly corresponds to all three at once:
⦁ Technological maturity: this determines the acidity and sugar concentration of the wine (and therefore its alcohol content).
⦁ Phenolic maturity: this corresponds to the ripeness level of the berries. It will therefore determine the quality of the color compounds and tannins.
⦁ Aromatic maturity: this determines the concentration of varietal aromas.
To check the maturity of the grapes, berries are sampled from each plot. Some are analyzed, while others are tasted. Then, an official decree sets the official start date of the harvest: this is called the harvest ban.
The dates vary by region but generally correspond to the following periods of the year:
⦁ Late August: Provence, Languedoc-Roussillon, Corsica. Generally, the harvest is earlier in the South.
⦁ Early September: Rhône Valley, Beaujolais.
⦁ Mid-September: Loire Valley, Burgundy, Bordeaux, Rhône Valley, Jura, Bugey, Savoie, Centre, Southwest.
⦁ Late September: Champagne, Alsace.
⦁ Early October: Cognac, Charentes, Lorraine.
Other Types of Harvests: Beware of Confusion!
There are other types of harvests that do not correspond to the classic definition of grape harvesting but still bear the same name.
Green harvests: During July, some winemakers decide to remove some still-green grapes from the vine. They are handpicked to relieve the vine so it has fewer grapes to nourish. This results in a lower volume of production but better quality. Indeed, removing grapes allows the remaining ones to increase their concentration and promote their ripening. However, be careful not to do this too early, as the remaining grapes may then tend to grow larger than usual, producing the opposite effect to what is intended.
Late harvests: Some regions choose to harvest later, in mid-October, to obtain riper grapes and therefore higher sugar concentration (for white wines only). This is notably the case in Alsace for varieties such as Gewurztraminer or Riesling, or in the Southwest with Jurançon. This also affects the wine’s color, which tends more towards straw yellow.
There are also very late and exceptional harvests in Alsace, Austria, Germany, and Canada, which take place in December or January. These produce what are called ice wines. The grapes must be very ripe, and the juice inside the berries must have frozen (temperatures between -6° and -12° are required). The grapes are then pressed while still frozen, and the juice is left to ferment. This produces a very sweet wine, which should be served at 6°C as an aperitif, dessert wine, or with cheese. Because the harvest is late, there are more grape losses and the harvest costs more due to the cold. This makes ice wine a precious, rare, and hard-to-access product because of its price.
