So, it's been hot. Hot and dry. Hot and humid. Hot. It seems like winter is a forgotten dream of sometime in one's past when one actually wore pants and sweaters and, oh, jackets! I remember those! Southern California has been in drought for over four years, and the last two calendar years have been the hottest on record. Climate change is here, and its consequences will have drastic effects on how to make wine under this new dynamic.
Wine has a love affair with water. Most vineyards in California thrive only because of irrigation. All wineries use copious amounts of water to clean what is a sticky, messy process of getting grapes to give up their goodness. With a decreased amount of rainfall, snowpack and available aquifers in the future, the battle between agriculture and urban/suburban areas for water will get worse. This is not an if, but a when. Since most people are pretty clueless as to where their food comes from, they don't understand that to grow food you need water, lots of water. Most berries and veggies are literally tiny packets of sugar-water encased in cellulose and fibers. Now, other industries use ridiculous amounts of water, including power plants- If you want to use less water, unplug your TV. Regardless, farmland is being encroached upon at a steadily, increasing pace, so to be good neighbors, farmers and vineyard owners need to lower their water usage. Like ripping out your front lawn, it's a sign that you are, at the least, aware of the problem.
In places with a long history of grape-growing for wine, there is a consistent theme: the rich, fertile soils of the valley floors were reserved for food production and the poorer soils or rocky slopes above were left for the vines. Not only is this a wise use of available space, but vines make better wine in places where vigor doesn't run rampant. If you look at Burgundy you will see this model in action for the last millennium. Burgundy, though, is not much like California. It has a Continental climate and abundant rainfall scattered throughout the year. Our Mediterranean-like climate has mild temps year-round and rain almost entirely in the winter months. We face a different set of challenges.
Dry Farming, what is this? Well, like it sounds, certain crops may produce their bounty without additional irrigation. Oftentimes, the berries themselves are smaller, with more color and flavor concentration, but a smaller crop overall. Variation from year-to-year is accentuated and there is no insurance available from having drip or flood irrigation. There are many factors to consider and one needs to plan on dry-farming at establishment of the vineyard, not later. Winegrapes for the most part are grown on American rootstocks, with a Eurasian scion grafted to the top. This protects the vine from native pests and diseases while still making use of the varieties of grapes that have proven to make the best wines. Rootstocks are varied and each has its own inherent vigor, and strengths and weaknesses. Rootstocks for dry-farming, in general, are more vigorous with deeper root systems, able to look for subterranean water. Common rootstocks for Pinot Noir suitable for dry-farming would be 110R, 1103P, 140Ru and even St. George, good old Vitis rupestris. Of course, rootstock selection is quite subjective and depends on the site and preferred methods of cultivation. Is one going to rely upon a cover crop to control vigor and stabilize the soil? What's the planting density going to be? Organic farming or conventional?
The main reason why people don't dry-farm is economics. One's crop size can go way up or down depending on the amount and timing of rainfall. Some vineyards that don't use irrigation cropped at around 0.3-0.5 tons per acre this year, well below the 2-4 tons per acre that irrigated vineyards received. This is difficult to swallow when one just spent $25-$40k an acre establishing a vineyard after purchasing the land. Wine would have to be proportionally much more expensive to take this sort of hit, year after year. Basically, the way it's set up now, water is cheap. Too cheap and relatively abundant to force growers into more efficient methods.
Wineries themselves use tremendous amounts of water cleaning the facility, much, much less than breweries, but still lots of water. Most managers have out-dated and lazy views on cleaning protocols and are unwilling to spend money to improve the facility and make water usage reduced. You will still see many people hosing down concrete pads rather than getting a broom out. Again, water is too cheap. Make it expensive and then all the CFOs will start buying brooms and checking the production team on water usage.
To conclude, dry-farming will become more commonplace as aquifers go dry, like many have in the Central Valley and in Paso Robles. Water will become more expensive to buy and then, and only then, will the majority of people start to care about conservation. Vineyards in Southern California will have a harder time adapting to new climate conditions, as average rainfall is less and getting smaller with the passing years. New technologies will help save water, but really it's taking the small steps now and planning for a drier, hotter future. Grab your broom and let's get started cleaning up this mess.