Vintage Update- 3-13-2012- Spring Ahead
Growers have been challenged in 2011 and 2010 with wet springs that make it difficult to control vine vigor as well as fungal diseases such as powdery mildew and Botrytis. Canopy management and disease prevention costs were high. It would be a relief to growers to not have to repeat those challenges and have better control over vine vigor in 2012, if, and only if, there is significant water to sustain the vines through any extreme periods of heat and to establish young vines in this era of significant replanting. Although vines can live with minimal irrigation, and growers often benefit from being able to control vine vigor through minimal and timely irrigations, insufficient water can be detrimental to vines accustomed to irrigation and can cause issues with low vigor, and overexposed fruit that may burn or shrivel.
The other concern about low water availability is for growers who use sprinklers for frost protection. This season may turn out to be a long and challenging frost season, since high pressure systems with clear skies have dominated leaving sunny days with cold, frosty nights. Budbreak is early, meaning this frost season may last longer than usual. Growers in less frost-prone areas will get better sleep in the next few months, and those with wind machines are in a better position than those with sprinklers as long as the inversion layers remain strong and the temperatures do not drop down too low. This may be the year to invest in orchard heaters and/or back-up wind machines if sprinklers have been your primary method of control. It is virtually impossible to even find a wind machine to rent. And get your mowers out, as tall cover crops will impede air flow and cause even greater frost risk!
Another long-term consideration about drought comes to mind when thinking about California’s most recent drought year of 2008 when wildfires burned throughout California. Napa already experienced a fire in the hills late this February when a controlled burn got out of hand on a dry, windy day. Fortunately, it was controlled overnight and there was little property damage and no one was injured.
What is ironic is that although these concerns are all reasonable given the current knowledge, we cannot predict the weather. Even weather forecasters have a hard time doing so, but they are currently forecasting some rain and unsettled weather this week. Significant rain this March and into early April will benefit us by filling the soil profile and reducing the frost risks. Let’s hope it comes now and not later in the spring when it challenges growers with high vigor and increased risk of diseases.
Most of my vineyards have not quite experienced budbreak yet, but judging from the level of bud swell, Chardonnay, Pinot noir, Malbec, Tempranillo and other early blocks and varieties will experience budbreak within the next week or so. This is a little bit early compared to ‘average,’ and significantly earlier than the two prior late years of 2011 and 2010.
At this point, lets remain optimistic that this week's weather events will fill our soil profiles and that overall the relatively dry winter will at best give us less concerns for vine vigor and disease prevention and allow us the flexibility to irrigate as needed and produce winegrapes with better concentration and riper maturity.