Inside Knights Bridge
Veraison - The Surge To Ripeness
Right now in our Estate Vineyard, grape clusters are going through an exciting process called veraison. Learn more about veraison and what impact it has on winemaking and harvest.
From mid-July to early August grape clusters go through a process called veraison. The grapes turn soft, change color and begin to increase sugar levels. Prior to this period the individual berries are green, hard and have accumulated only about 6% sugar. But after veraison sugar can raise to nearly 20% within a few short weeks. Additionally, during this time the grapes develop complex flavors and build colors: red varietals turn purple to black, as seen in the above photo of Cabernet Sauvignon from Block 4 of our Estate Vineyard. White varietals, such as Sauvignon Blanc and Chardonnay, turn from an opaque emerald green to a beautiful translucent golden green. It is impressive to realize that the grapes, through photosynthesis, will generate about a ton of sugar per acre.
During this critical time in grape development and maturity, the grapes need warm days with temperatures between 85°-95° F during the day and 65°-75° F at night for optimal development.
Every vineyard manager fears rain during this time since it can cause rot on the fruit. Nevertheless, the vines need water, so the irrigation regime must be carefully controlled throughout the growing season. Too much water can pump up the bunches with excess moisture and maybe even cause the vines to start growing new leaves and shoots, which diverts focus and nutrients away from the grape clusters. On the flip side, too little water can cause defoliation, wilting and the vines to stop producing sugar. In our estate vineyard, we use a water monitoring service that comes out and checks the vines to determine the optimal amount of water that is needed for each vineyard block (This process is called "Pressure Blocking" and we'll cover this topic in a future journal entry.)