Summertime may be filled with vacation, pool-lounging, and rosé-sipping for us, but the hottest months of the year are anything but relaxing for wine grapes and their caretakers. While winemakers anxiously await harvest in September, they are busy taking measures to ensure that their grapes have the best possible growing conditions throughout the summer. Read on to find out what happens in the vineyard while school is out.
Flowering (May and June): By the time school lets out in early June, the small flowers on a grapevine have begun to self-pollinate and set the stage for baby grapes to grow.
Fruit Set (June): After the flowers on the vine have been pollinated, small grapes begin to grow. From this point on, a winemaker or vineyard manager may decide to cut clusters of fruit off the vine, called "thinning," so that the vine can better concentrate its energy on growing a few grape clusters, and therefore concentrate the flavor of the wine too.
Veraison (July and August): Veraison is the scientific name for the period of time when red grapes change from green to deep purple. Winemakers may still be thinning clusters of grapes in July and August, and also the cutting off the leaves of the vine in strategic places to allow more sunlight and air circulation around the grapes.
By the end of summer, the kids are back in school and the grapes are almost ready to be harvested. Harvest usually happens about 100 days after flowering, but the winemaker or vineyard manager makes the final decision based on acid and sugar levels, ripeness of tannin, and by the old-fashioned "does it taste good?" test. Check back in a few months for a report on harvest 2013.