The extreme weather swings in the final week of June, an unusual inch or more of rain followed by 100 degree+ temperatures, have unsettled the nerves of most farmers in Sonoma County. Fearing mildew proliferation throughout the vines has forced many to apply an extra spray to the vines to help stave off mildew or to attempt to combat the mildew that has set in.
Mildew at this stage of the grapes' maturity is troublesome but not the end of the world. The grapes have not formed any sugar yet, and should not rot. The mildew can degrade the quality of the fruit, and if left untreated, can render it unfit for winemaking. However, by “opening the canopy” leaf pulling we expose the fruit to air movement which helps in fighting mildew.
Due to the 100 degree plus weather, we have opted to start our workday at 3am to avoid the afternoon heat, and we do as much leaf removal as we can. We should see temps cooling down by next week, and most of July we will slow down the work a bit, and wait for fruit to ripen. We anticipate harvest to start around mid August (a bit early compared to previous years, but not out of the ordinary).