30 Jul Color explosion in Valley vineyards
A French viticulture term; veraison means “the onset of grape ripening.” It involves a number of changes in the grape. First, the grapes start to change color. Once veraison starts, the vineyards begin to explode with different shades of yellow, red, and purple.
Every grape variety begins its journey green in color. The untrained eyed won’t know a red or white grape until it reveals its identity at veraison. Growers in the Yakima Valley typically see the grapes start to change color in late July or early August.
White grape varieties change from deep green to a soft, translucent, golden-yellow color. Red grapes are visually more dramatic. Transitioning from a similar green color to bright ruby-red or, depending on the variety, deepening further to a deep red, almost black color.
During veraison, sugar in the grapes increase dramatically, from a tiny amount to about 23% at harvest. As veraison progresses the sour acids (acidity) in the grape start to break down. The grape begins to change from being very tart and acidic to tasting more fruity and complex. Aroma and flavor components also begin to accumulate in the fruit.
In addition to long days and warm sunshine, the Yakima Valley experiences wide diurnal temperature swings; the variation between daytime and nighttime temperatures. These swings can be as much as 30-40 degrees Fahrenheit. The day to night temperature change is one of the many reasons that the Yakima Valley is an ideal place to grow fine wine grapes. The heat of day promotes ripeness and sugar development, while the cool nights help the grapes retain acidity and freshness, resulting in balanced flavors.
The ripening process takes approximately 40 days-depending on the grape variety, location, weather, and farming practices. In many vineyards, harvest begins in August with Sauvignon Blanc, an early ripening grape, and ending with Cabernet Sauvignon harvest in early November.
How do you know when it’s time to pick? Winemakers use a variety of methods for testing when grapes are ready for harvest. The process begins and ends with tasting. Vintners are looking for specific flavors in each grape variety. Measurements of the pH, sugar and acidity levels also help determine when the fruit is ready. But the final decision to pick is made via the senses. Winemakers can taste the grapes every day and suddenly there is a new complexity and multi-dimensional character in the grape. That is the signal. Harvest begins.
Based on the onset of veraison this year, growers in the Yakima Valley expect harvest to begin early to mid-September. Research shows this year’s temperatures are consistent with historical averages, meaning the ripening and harvest timelines will be normal for the 2017 vintage. The overall harvest is estimated to be smaller than last year, but the quality looks exceptional.
If you are interested tasting grapes and learning more about wine grape harvest, consider participating in Catch the Crush, the local harvest celebration October 14-15, 2017, or contact your favorite winery and ask if they provide vineyard tours.