E&J Gallo Winery purchases The Ranch Winery in St. Helena.

E&J Gallo Winery capped off a busy year of acquisitions on Wednesday by announcing a deal to purchase The Ranch Winery in St. Helena, giving the country’s largest vintner greater capacity in the North Coast premium wine region.

The Ranch Winery is located within 15 miles of Gallo’s two other Napa wineries, Louis M. Martini and William Hill, between Highway 29 and Silverado Trail. That location will give it the ability to handle excess capacity on large grape crushes as well any subsequent growth in Napa Valley.

Terms of the sale were not disclosed, though it further cemented the Modesto-based wine company’s aggressive push into the premium wine category that has been the hallmark of rival Jackson Family Wines in Santa Rosa.

Already this year, Gallo has purchased J Vineyards and Winery in Healdsburg and the historic Asti winery, one of the largest production facilities in Sonoma County, along with the Souverain brand. It also bought a Monterey County winery and 525 acres of highly regarded vineyards.

The Ranch Winery is a large custom-crush facility that can handle up to 30,000 tons of grapes per year, giving Gallo an overall capacity of 45,000 tons in Napa County. It also has the ability to bottle up to 4.6 million cases and about 8 million gallons of storage.

The 70-acre property has 26.5 acres of cabernet sauvignon and merlot grapes, though they are under long-term contract, said spokesman Lon Gallagher. All contracts under The Ranch Winery will be honored with its existing customers, he said.

The purchase comes as Napa County officials debate whether to put restrictions on wineries given concerns over growth and traffic. But any regulations would most likely apply to new facilities, making wineries with existing permits much more valuable, especially as the available land for the wine industry is increasingly scarce in the county.

With the latest purchase, scheduled to close on Dec. 31, Gallo owns 15 wineries in California and Washington. The 80 employees of The Ranch Winery will be interviewed for employment at Gallo if they express interest, Gallagher said.

The seller was Rutherford Wine Studios.

You can reach Staff Writer Bill Swindell at 521-5223 or bill.swindell@pressdemocrat.com. On Twitter @BillSwindell.