March 24, 2008
Hey could you tell me what grape shatter is please? - Jeanie in Beaumont, TX
Grape shatter which is known as Coulure in French happens when a grape cluster does not fully mature. This is due from either the grapevine’s flowers not getting pollinated or that the berries fell off soon after they formed.
Coulure is triggered by periods of cold, cloudy, rainy weather or very high out-of-season temperatures and the condition is manifested in Spring. Varietals with high proclivity to couloure are Grenache, Malbec, Merlot, and Muscat Ottonel. Other causes of coulure may be vineyard conditions and practices, pruning too early or too severely, excessively fertile soils or overuse of fertilizers, and improper selection of root stocks or clones.
Coulure can also cause irregular bunches of grapes which are less compact than normal. These bunches are more sensitive for diseases. The yield of a vine with coulure will decrease substantially and is what is meant by the term “poor fruit set.”
See, this is why you should always be grateful for that perfect bottle of wine. Think of all the poor, poor souls in the past who literally had their hopes and dreams for lush moments shattered. Drink solemnly in remembrance of their loss. Amen.