The Pinot Noir grapes are starting to change colour from green to red. This is the start of the ripening process and in viticulture is called veraison.
Grape berries have two distinct growth phases. The initial phase is when the cells divide and expand and the grapes begin to swell and fill out the bunch. After veraison the acidity decreases due to degradation of Malic acid, making Tartaric acid the predominant acid. At the same time sugars (glucose and fractose) are accumulated and the volume of water entering the grapes decreases resulting in an increase in sugar concentration. The level of sugar accumulation in the berries is dependant on leaf photosynthesis which is why we could do with some more sun!
As the fruit ripens it becomes more attractive to the birds. As well as the KiteHawk and Helium Ballon we will be netting the outer rows of the vines early next week.