Frog’s Leap Winery owner John Williams (right) and viticulturist Frank Leeds discuss dry farming Tuesday during the Organic Winegrowing Conference presented by Napa Valley Grapegrowers.
—With minds focused on the prolonged drought, it’s not surprising that the seventh Organic Winegrowing Conference scheduled a session about dry farming. Nor is it a surprise that the dry-farming session was very well attended by attendees—even though, strictly speaking, dry farmers don’t have to be organic. (Most are, however.)
Ironically, noted iconoclastic but eloquent John Williams of dry-framed Frog's Leap Winery
, “Dry farming isn’t about saving water. It’s about producing better wine—and long-living vines.”
Williams acknowledges that dry farming saves water, too—he feels that most grapegrowers overwater vines.
The sold-out conference sponsored by the Napa Valley Grapegrowers
attracted 150 growers, winemakers and viticulturists to Inglenook
winery, one of the first 10 organic vineyards in Napa Valley. (Co-owner Eleanor Coppola noted that the ranch was certified organic in 1989.)
Dry farming road trip
Participants in the dry-farming session filed onto a bus that took them first to Williams’ Rossi Ranch, the most photographed and painted spot in Napa Valley, which currently is undergoing replanting of the head-trained vines near busy Highway 29.
Williams, his son Rory, winery viticulturist Frank Leeds and Leeds’ daughter Lauren Pesch led tours of the 52-acre ranch, which was first planted in 1866. Williams has placed it in a conservation easement managed by Land Trust of Napa County.
Williams pointed out that dry farming isn’t new. “All Napa wineries used to be dry farmed. The famous historic vineyards and great wines that first built Napa Valley’s reputation weren’t irrigated.”
He noted that in the late 1960s, overhead sprinklers were introduced for frost protection, and growers dug ponds, but the focus wasn’t on irrigation. “There wasn’t enough water to use sprinklers for irrigation,” Williams said. Drip irrigation was invented in Israel during the 1950s and introduced to Napa Valley in 1972.
Dry farming in practice
The Rossi Ranch was planted on St. George rootstock, and Williams is continuing to use that practice. St. George is a Rupestris
variety long used in dry-farmed California vineyards because of its deep and extensive root system. The vines are field grafted with wood from Martinez Orchards
in Winters, Calif., and Williams was effusive in his praise of the nursery.
Williams is replanting the ranch including some areas that were pasture and never planted. In addition to lucrative Rutherford Cabernet Sauvignon, he is replanting historic varieties including Mourvedre, Zinfandel, Carignan, Sauvignon Blanc and even Riesling. “It helps to have a wine club whose members like to try different wines,” he admitted. Some of the grapes go into a rosé, due to its light color.
He lets the land lie fallow for 18 months before replanting, growing an unirrigated cover crop of legumes, vetch, fava beans and other plants that are disked into the ripped soil.
The vines aren’t watered except to get them started. They receive 5 gallons by hand in a pit during April and at the end of June of their first year, then one watering the second summer. The pit is covered after the watering, and Williams acknowledges that the hand labor doesn’t encourage overwatering—either by his vineyard workers or the one paying for the labor.
The ranch is on the valley floor, which is considered rich in soil and water, but Leeds said that the water table in dry summers is about 25 feet down, though it rises to 5 feet during a wet winter.
By the numbers
Many growers seem to think dry farming produces poor yields, but the ranch averages about 5 tons per acre. The vines have to be thinned to achieve that, but Williams points out that it’s dropping much less fruit than in irrigated vineyards, where half the crop may be discarded.
Leeds calls the cane tips his “water probes,” and they are growing and vital in spite of the drought and dry farming.
He said that the vines need 16 to 18 inches of rain per year, not the 30 inches that Napa Valley typically receives. “The rest just goes into the creeks,” he stated.
Williams tends to anthropomorphize vines in explaining why dry farming works—and produces what he considers superior wine. “You have to think like a grapevine. Its job is to produce bright red or aromatic white berries that attract birds that eat them and accidentally distribute their seeds, then the vine has to prepare for the winter. The vines take clues from their environment; the tips of their roots and canes are the brains that tell the vines what to do.”
He continued, “If you give them water, their roots stay close to the surface and need watering more often. You cut off their tops, remove crop, cut down the trees that provide hints, kill the insects and microbes and chase away the birds. What you produce is dumb vines.”
Williams pointed out that grapes used to be ripe at 22° or 23° Brix and produce 13% alcohol wine. “Now the vines are cut off from their information sources, and they just keep producing more and more sugar because they don’t get signals to stop.”
The second stop on the tour was the Garden family’s White Barn Vineyard, which (unlike Rossi) is not on the valley floor but on a mild bench. Frank Leeds, who manages Frog’s Leap vineyards as well as his own vines, oversees 40 acres of Zinfandel planted at White Barn Vineyard on St. George rootstock in 1978. “We took over in 1997 or ’98 and stopped irrigating, yet we still have to work to get 5 tons per acre instead of 6 to 8 tons.”
Williams added, “When we took over it was 40 years old, but the crop was uneven, ripening was delayed and we had rot. We thought we’d have to replant it. But after converting to dry farming—and there’s no high water table in this area—it became much healthier. The vineyard should be good for another 40 years.” It also gets the traditional flavors of Napa wines at 13.5% alcohol.
Williams suggests that irrigation may even have contributed to the spread of phylloxera. “Irrigating vines brought roots close to the surface, into the zone phylloxera inhabits.”
He added that St. George is too vigorous if irrigated, which is one reason people are using other rootstocks. It’s more difficult to convert these new, mostly riparian rootstocks to dry farming, however.
Other growers also spoke about their experiences dry farming. Mike Chelini in the mountains at Stony Hill Vineyard
and Stu Smith on the mountain tops at Smith-Madrone Vineyards
, and Tod Mostero at Dominus
on an alluvial bench near Yountville.
Smith just expected he would dry farm when he started in 1972, though he experimented with drip irritation. He found it a nuisance and removed the tubing, but now he irrigates new vines for a few years. “We get smaller berries and a better skin-to-juice ratio.”
Chelini says Stony Hill never irrigated its vines. They’ve never used synthetic herbicides or pesticides either, for that matter.
Dominus’ Mostero started in France, where vines weren’t irrigated, so he never felt dry farming was a big issue—though he admits that this year, they’ll water about 2 % of the vines by hand due to the drought.
This minimal irrigation inspired Williams to remind the audience, “Dry farming isn’t a doctrine or ideology. It’s just a way of farming.”
As a final part of the demonstration, Leeds demonstrated a French plow for removing weeds under vine rows and a sprayer. He and Williams also showed a cultivator, a machine rarely seen in Napa vineyards. “A cultivator can replace one irrigation,” he said.