| California once grew drought tolerant grapes, and it may have to once again. (Hat tip to blogger Elfling for pointing me to this old but relevant article.) Following the introduction of drip irrigation in the 1970's, growers were eager to control the amount of water their vines received and - to best do so - planted water-loving riparian varieties of grapes in the 1980's. Despite the fact that Napa is a dry area, they somehow assumed that water for irrigation was an unlimited resource.
"If you're a grape grower, you want to have that vine dependent on what you do so you can manipulate them," says Williams, whose academic work focuses on irrigation management. Williams further explained: "Since the vine is getting most of its water from the drip system, then a grape grower has greater control on how much the vine gets water."
The other objective for replanting was to mirror the density in Bordeaux and Burgundy, up to 2,500 vines per acre instead of the previous status quo of 450. Vines competed for the soil's water and prompted the need for 100 to 200 gallons of water per vine per season -- each vine typically produces two to four bottles of quality wine per year. Though water consumption in California rose as a result, replanting helped revive the state's fine wine industry, and the practices became standard.
With this year's drought, I can only imagine that many more vintners are considering ditching irrigation. Those who rely on heavy irrigation are hurting, while those whose grapes grow with natural rainfall can still thrive. However, as the article points out, this isn't a change that can be made overnight: "if California returned to dry farming, vintners would have to rip out rootstock, replace with drought-resistant types and replant vines farther apart." Looks like we made our beds in the 1980's and beyond, and we are now lying in it.