Dr Vino's wine blog

Last Thursday, I stopped by Hirsch Vineyards where Jasmine Hirsch told me that flowering was the second latest–and the latest was just last year. Given this year of wacky wine weather, I thought it was worth asking the question: What is flowering and how does a late flowering affect the finished wine?

To further reproduction, the vines burst flowers that become bunches of grapes. The period between flowering and the arrival of the grapes (called “fruit set”) is a tenuous time when severe weather can damage the emerging berries, so the shorter the period between bloom and set, the lower the risk to the harvest’s quality and quantity. Jasmine said that in 2005, they had an early bloom and a late set with heavy rains in between, which reduced the yields to a half a ton per acre, or 20% of the normal yield. By contrast, even though last year was their latest bloom, the fruit set relatively fast and the window of potential peril closed quickly. (And the wines in the barrel appear to be evolving well–more on that later.) Whether that will be the case again this year, nobody knows. But the late bloom did at least avert the storms of late May and early June that may have caused “shatter” in some other, warmer Northern California areas that had already had bloom. However, a late set may mean a late harvest, with its attendant risks. Mother Nature is capricious and, despite the efforts of vineyard owners like the Hirsches, ultimately runs the show.

The photo below is from a row of grapevines that have not yet flowered while the above photo is just across the row and shows that flowering has started in Block 8 pinot (pommard, planted in 1993) at Hirsch.