Don’t get too hung up on planting the right clone, say two noted wine industry members from Washington State. Years of collecting wine grape clonal data from both the vineyard and bottle have yet to show a best clone for the state.
“If you’re planting a new vineyard site, we recommend planting multiple clones,” said Russell Smithyman, director of research for Ste. Michelle Wine Estates, the state’s largest wine business. Smithyman has spent more than a decade researching wine grape clones, collecting vineyard and wine data from a wide variety of clones grown in replicated trials. He oversees vineyard and wine research at Ste. Michelle, including a 7.5-acre variety trial that has 92 varieties and clones under test.
“In the beginning years of Washington’s wine industry, everything was mono-clonal,” he said, explaining that in most instances, a single clone was planted for each variety and they were chosen for productive reasons. “Most clones came from California, and at the time, it really didn’t matter what clone was chosen.”
As winemakers and consumers began paying more attention to specific clones, Ste. Michelle began a clonal research trial to learn about differences between clones, collecting field and wine quality data. Research wines from clones have been made for many years, using the same yeast and fermentation schedules to allow true comparisons from grapes and wine handled in the same manner. For example, three clones of Merlot (1, 3, and 8) have been grown in replicated trials and made into research wine for several years.
“Ste. Michelle has collected data on all kinds of things, conducted blind tastings, looked at winter damage, and now we make research wines every four years to add to our body of data,” Smithyman said.
After a decade of testing, Smithyman said the only clone he can pick out visually in the vineyard is Merlot 3, which has bigger berries and clusters than clones 1 and 8.
Through the years, a few clones have stood out and have seemed to shine, he said. Merlot 3 and Cabernet Sauvignon 8 are two examples.
Smithyman and Jeremy Santo, winemaker for Milbrandt Vineyards, shared their views during a clonal wine tasting of Merlot held in conjunction with a summer grape field day sponsored by the Washington Association of Wine Grape Growers.
Santo added that Milbrandt is still trying to decide which clones they like best and where they grow best. “But as a winemaker, having different clones for blending is awesome,” he said, noting that Milbrandt keeps clones separate during fermentation until the blending process.
Clonal research takes generations to develop and is expensive because of the time involved. While Washington’s wine industry is still sorting out differences between basic clones like Merlot 1, 3, and 8, California is now testing clones with triple-digit numbers, Smithyman said.
“There’s new stuff out there with triple digits that makes our clonal numbers so passé,” he said. “We’ve built our industry on Cabernet 8 and Merlot 3—clones that didn’t work in California because they were too productive—but they’re working fine for us.”
Smithyman gives Washington growers a lot of credit when it comes to creating their own diversity and quality within a vineyard. “Clonal diversity can be helpful, but so much of what we can do in a vineyard with canopy and irrigation management can add quality and complexity to the grape quality. So much of what we do to improve grape quality overshadows the nuances of clones.”
The bottom line, he says, is to plant multiple clones to give your winemaker blending choices. And, don’t get too worried that there’s only one right clone. The industry is still collecting data on how clones perform at specific sites.
“If you’re planting a new vineyard, say in Red Mountain, we don’t really know the best clone there. But we do know some characteristics of Red Mountain, it being a very warm site that produces strong tannins. That could be used in choosing a clone depending on what the winemaker wants to accomplish,” he said. Winemakers might want to emphasize or minimize the tannins and could choose a clone reported to do that.