Winemaker's Journal
August
Cabernet grape clusters in August during veraison. The term veraison refers to the softening of the grape berries and, in the red varieties, their change from green to red. I have always thought that it was a contraction of the French words vrai raisin – true grape. Whether I’ve made up that etymology or not, it is an accurate description, because its hard to think of those hard green marbles of June and July as grapes. When they turn red you’re tempted to try one. This is not usually recommended in early August… boy are they sour, but a few weeks later they’re delicious.
Veraison is a key marker in the season. On average, Cabernet harvest will start 45 days from 50% veraison. We use it in crop estimating too, because we know how much weight a cluster will gain from veraison to harvest, so we can take veraison weights and get a very good crop estimate. Finally, we can use veraison to indicate if the vine is carrying too heavy a crop and use it as a guide for thinning. This is commonly referred to as a “green drop”. After the berries have softened the juice composition is much more influenced by climatic conditions, so the weather throughout August has a direct influence on the quality of the vintage. This is when the viticultural rubber hits the road.
The early summer of 2009 has been quite mild and the vines are in beautiful balance. 50% veraison looks like it will be around August 5 in most Cabernet vineyards. This will put the beginning of harvest around the 15th of September, which is close to average in our experience. This is when it starts to get exciting!
