A centuries-old farming technique called dry farming — once the order of the day in California’s Central Valley — is once again drawing the interest of some of the region’s farmers.

The technique is as simple as it is risky. Dry farming relies solely on rainwater to keep crops growing throughout a dry season.

Used for centuries in the Mediterranean region to grow crops like olives and grapes, the technique is not for the faint of heart. A year with a dry winter can devastate crop output and put an onerous dent in a farmer’s wallet.

“Dry farming would be a hard life because you’re at the whim of the rains,” said Jay Lund, director of the Center for Watershed Sciences at the University of California-Davis. “It would have to be a fairly small-scale farm, and in some cases, it would be a good road to poverty.”

Yet dry farming has its adherents. Many are small farmers and vintners who either lack irrigated water or believe that dry farming produces better-tasting fruits and vegetables.

“I think people are interested in the idea,” said David Runsten, policy director of the Community Alliance with Family Farmers.

Runsten recently promoted dry farming to a consortium of California farmers. “We’re promoting it because we think it makes for better wine,” he said.

But sustaining the viability of farms is also an issue. Runsten cited a CAFF study that found that the 250-acre Frog’s Leap vineyard in California’s Napa Valley conserved roughly 64,000 gallons of water per acre through dry farming each year.

“We’re pumping a bunch of groundwater to produce cheap wine in California right now,” Runsten said. “I don’t know if that’s sustainable.”

A recently released study from researchers at the University of Texas warned that the current depletion rate of the Central Valley aquifer, the large storage of underground water farmers use for irrigation, is unsustainable — even when wet years follow dry ones.

Currently, nearly half a million acres of land are devoted to wine grapes in California. Of those, about 2,000 acres are dry-farmed; the rest are drip-irrigated, said Runsten.

Because dry-farmed fruits and vegetables need more space between each tree, it can prove a costly endeavor.

But such spacing means roots spread out farther, which results in healthier trees and vines as well as more intense flavor, said Jeff Maine, who farms in California’s Capay Valley.

He said he saw the superiority of dry-farmed fruit when he dry-farmed a 100-year-old heirloom apricot orchard alongside Putah Creek, just west of Winters, Calif., between 2003 and 2010.

“The dry-farmed stuff has a whole different flavor,” said Maine, who co-owns the farm Good Humus Produce, with wife Anne Maine.

“People really respond to the traditional aspects of it.”

The popularity of Maine’s apricots was not lost on Sacramento (Calif.) Food Co-op general manager Paul Cultrera, whose store sold the apricots.

“Annie and Jeff’s apricots are worth any price,” said Cultrera. “They’re that good, and that much better than whatever others we sell.”