From the OC Register:

There’s only one little problem: much of California’s 450-mile-long Central Valley doesn’t benefit from the diurnal swing that brings cool nighttime temperatures to vineyards – conditions that many desirable varietals need.

But the valley’s grape growers are undeterred. They think success hinges on finding the right kind of grape to grow in its hot, dry climate.

San Joaquin Valley wine grape growers met in Fresno on June 14 to study the challenge at the 5th Annual Viticulture and Research Roadshow, presented by UC Cooperative Extension and the San Joaquin Valley Winegrowers Association. They agreed that there are no easy and obvious choices.

“We haven’t found that shining star yet,” Oren Kaye, winemaker with Constellation Brands in Madera, told the Western Farm Press.

But it could be out there. There are hundreds of red and white varieties (technically called cultivars) to choose from; some come from regions that share the climate characteristics of the San Joaquin Valley (the southern segment of the Central Valley).

For more, see: Central Valley farmers look for the perfect grape