Steve Thomas, vineyard-operations director, looks over flowered clusters in a drip-irrigated vineyard at Kunde Estate.
Eric Risberg / AP Enlarge
KENWOOD, Calif. - Vineyard manager Steve Thomas grasps the trunk of a zinfandel vine, a redwood of the vineyard, gnarled with age and planted in the days when irrigation meant a barrel of water on a horse-drawn cart.
The workhorses and the carts are long gone. But these old zin vines at Kunde Estate in Sonoma County still get water the old fashioned way: rain, dew, and a deep root system.
They call it "dry farming," which is what agriculture used to be before plastic hoses hooked up to a water supply made deserts bloom. A few vintners are returning to it.
They are driven by concerns over dwindling water supplies, the belief the system produces more intensely flavored fruit, and, in Kunde's case, a desire to return to old traditions.
"What you find out is grape vines are incredibly adaptable," Mr. Thomas said. At the 600-acre Kunde Estate, about 100 acres are dry-farmed.
Wine grapes are grown without artificial irrigation in parts of the world such as Spain and France, where some regions forbid irrigation, said Robert Wample, chair of the viticulture and enology at California State University, Fresno.
Dry farming in California is unusual, although there is a trend toward using less water.
"We're learning to be much more precise early in the growing season so we can control the vegetative growth, minimize the total water consumption, and follow that with good management practices," he said.
Less water means more intensely flavored grapes and wines; too little water leads to raisins.
Mr. Wample, who has studied irrigation techniques for years, sees irrigation as a useful tool in the winegrower's arsenal, although he agrees careful water management is critical because of concerns about climate change.
"The challenge is understanding how to best utilize water as a management tool," he said.
Dry farming starts before the vines are planted, said John Williams, founder and winemaker at the Frog's Leap winery in the Napa Valley and a champion of dry farming.
Farming dry means more than not irrigating, he said.
"It's an active form of preserving moisture in the ground so you don't need to irrigate."
That turns out to involve getting up close and personal with dirt as fields are carefully cultivated, mulched, and kept under scrutiny.
"Oh, it's filthy, dirty work," Mr. Williams said with a rueful laugh. But the reward, he believes, "is wines much more deeply connected to the soil, wines much fuller in flavor."