Rogue hot day trashes vintage 2010
Photo by George MacLeod
Tuesday, Aug. 24, began as a welcome day, finally without fog. But by noon it was clear as temperatures steadily climbed to 106 degrees that this was a disaster for the vines and their grapes. By late afternoon most of the grapes on the west side of the vines had been severely sunburned. These grapes could not be harvested and would have to be removed. Overall loss could reach 20% of the expected harvest! Grape clients cannot accept sunburned fruit, as it adds raisin flavors to the wine.
Angry vines demand reform
That next morning as manager Chuy and I toured the vineyard to survey the damage it was clear that the vines and their vineyard spokesvines, Marie and Javier, were in a surly and angry mood. The vines all feel that our cultural practices all season just set this up. This great loss was forecasted, and management heads should roll and a new management team be installed.
Reader, you be the judge
Up until Aug. 24 we had weeks on end of cold foggy mornings with the sun making a belated appearance sometime between 10 a.m. and noon. In grape growing, we keep track of the number of “degree days” that the vineyard accumulates. This is done by counting how high the daily mean temperature is above 50 degrees. For example, if the mean temperature on a given day is 70 degrees, this would be 20 degree days for this day. The average yearly total required for ripening grapes in our area is approximately 2,950 degree days. As of Aug. 13 we had accumulated only 1,677 degree days, or only 57% of what is desired to keep our grapes on track for a timely harvest.
The consensus among Sonoma Valley grape growers is that we are at least two weeks behind and perhaps three weeks behind normal. This is not some academic doodling. Each day that harvest is pushed later into the fall, the risk increases that we could have quality-destroying rains before the grapes can be picked. These days and days of cold, foggy weather have been ideal for mildew and bunch rot, so we have been playing defense all summer. This has meant that we took off more leaves to open up the vines to more sun and air.
Deleafing is generally done right after bloom time and fruit set, and in a normal year the tiny growing grapes become adjusted to sun and air. Normally we do not take off any leaves on the west sides of the vines, to protect the young grapes. This year, because of disease pressure, we removed some of the west side leaves and deleafed twice, removing leaves the second time that had been shielding grape bunches. Plus, we did some thinning and some adjusting of individual bunches so that they would get more sun and air. And until the disastrous hot day, all this was working. We were disease free and slowly moving towards harvest, which we expect to be two to three weeks late. To be honest, all of us were a little nervous about any deleafing on the west sides, but in a normal year even with west side deleafing there is very little sunburn, which can be easily managed.
The true culprit
The bad actor behind all this stress and worry and finger pointing is Mother Nature. She is a regular participant in our Board Meetings for our vineyard. But often she is not a team player and cannot be depended on to play by the rules. She regularly throws weird and difficult cards on the table just to see how we will react. With this disastrous hot day she must be pleased with herself.
Some good news
We continue watching our moth traps and to date have not seen any of the dreaded European Grape Moth in our vineyard.
More good news
The market for wine grapes is awful, but through luck, hard work, or divine intervention, we have contracts for all our grapes this fall. We may not be getting the prices we would like, but there is a huge wine grape surplus out there in this now-globalized market, and as they say, “…any port in a storm.”
And finally the “So there”
I don't like to air our vineyard problems in public but I must add that until the “HOT” day, Marie, Javier, Chuy and I all believed we were on the right program, considering the cold foggy year. And, mea culpa, the deleafing to defend against disease did seem like the right program, that in turn with the awful HOT day did facilitate and cause some of the severe sunburn. Growing grapes with a partner like Mother Nature is a dangerous venture. And for Marie and Javier, some decent Indian summer weather might indeed help us recover and still produce a great vintage 2010.
Owner, Indian Springs Ranch and Vineyards
Email: george@kenwoodpress.com
