The official definition of veraison is “change of color of the grape berries”.
It represents the transition from berry growth to berry ripening. We first noticed this change for the 2020 season on July 10th in the Watson Old Vine Zinfandel Vineyard.
The green berries have zero brix (brix is the measurement of sugar level in the grapes), and the purple berries that we spotted were closer to 5 brix. We are looking for around 23 brix to harvest.
White grapes of course go through the veraison process as well, but instead of changing color, they become more translucent.
To see this process for yourself, we highly recommend visiting a vineyard in the Summer – late July or August is the best time to be able to spot this transition in the grapes.
Things are moving along very quickly this year!