Nick Frey, president of the Sonoma County Winegrape Commission, is seeing rapid vine growth in the county.
With increasing temperatures more like summer than spring and good soil moisture, the “vines are now growing very well,” he says.
Bud break on the earliest varieties started with the warm weather in February.
“In terms of heat units, the season started out colder than normal,” he says. “In some cases, bud break may have been two to three weeks later than usual. But, since about mid-April the number of heat units has been higher than at this point in the last two years, and now vines are catching up fast.”
Many growers are reporting an average of close to two clusters per shoot. As a result, Frey says, Sonoma County yields this year may return to more normal levels, with one possible exception in the southern part of the county.
“In the Carneros area some Pinot Noir vineyards aren’t quite as fruitful as other varieties,” he says.
Prospects for the crop overall are much more promising at this point than a year ago. “In 2011, we had cold weather during bloom, followed by rains, which resulted in a lot of shatter. We knew from the low cluster counts that we were off to a bad start. But it got worse. This year’s crop doesn’t look huge, but it could produce the best yields in the last two to three years.”
He’s expecting vines to start blooming on time in late May or early June.
Sonoma County growers have begun powdery mildew treatments. Dry weather once the vines started vigorous growth has minimized the risk of two other early-season diseases — phomopsis and botrytis — Frey says. Blue green sharpshooter counts are up in some areas this spring, increasing potential for Pierce’s disease infection, he says.
The low number of frost events this season has enabled growers to save water for irrigation later in the season.
“We’re still behind normal for rainfall,” Frey says. “But, we had some good rains in March and soil profiles are full. So, in terms of water availability, we’re off to a good start.”