Having just returned from the vineyards in Eastern Washington, I can report that veraison is underway. Veraison is when grape berries change color and texture on their way to ripening. Before veraison, the berries are hard and green, while after the berries are soft and red or light yellow, depending on the grape variety. This transformation is much easier to see in red varieties where it is easy to see the percentage of berries have changed color. In the picture to the left, about half the berries are either starting or are through the process of veraison. This picture was taken at Stone Tree Vineyard, Wahluke Slope, where veraison was the most advanced of the ten vineyards I visited this week.
Veraison can be a critical time for winemakers and growers. It marks an essential transition for the ripening process. There are a couple of thoughts on how long it takes between veraison and harvest, all of which depend on the area, weather and the grape variety. Some people say six weeks is a good measure, but it indeed can be longer or shorter. In any case, it is time to start getting the picking bins and tanks ready; harvest is right around the corner!
Veraison can also be an important time to start the process of ‘green thinning.’ Winemakers and growers work together to determine if the vine is in balance: is there the appropriate amount of crop on the vine for the fruit to ripen in a timely way and maximize quality? If the crop is too large, this is a particularly good time to trim some of the clusters as it is easy to see which ones are lagging behind. When the greener clusters are thinned in favor of the redder ones, it evens out the ripeness of the clusters on the vine and is an important quality consideration as it will lead to more uniformly ripe clusters when picked. Some varieties tend to ripen more evenly than others, so this process is more important in varieties that tend to have uneven ripeness such as Petit Verdot. It is important to time ‘green thinning’ so that you can see the lagging green clusters. Often this is when about 80% of the berries have completed veraison. On my latest trip, most of the vineyards were still little early for green thinning to occur. I will be returning in a few weeks to walk the vines and talk to the growers on how to proceed.
~Brian Carter, Winemaker