Ste. Michelle Wine Estates, Washington’s largest wine producer, first experimented with growing wine grapes organically more than a dozen years ago, taking on the trial as a challenge. That "challenge," which began with 45 acres, has grown to about 380 acres, resulting in nearly 16,000 cases of "Naked" wine made with organic grapes.
"We had a whole section of grapes where we weren’t getting the quality or quantity that fit our different wine programs," said Derek Way, viticulturist at Ste. Michelle’s Columbia Crest Estate Vineyard in Paterson. A white Riesling block was chosen to learn if grapes could be grown organically. The block was farmed according to organic regulations for ten years before it was certified organic in 2004.
When Way joined Ste. Michelle four years ago, one of his priorities was to comply with the organic certification requirements and achieve certification in several varieties. By the 2007 harvest, a total of 156 acres of Riesling will be certified organic, as well as 100 acres of Merlot, 11 acres of Cabernet Sauvignon, and 111 acres of Chardonnay.
For Way, one of the hardest parts of going organic has been expanding the nearly 50-acre experiment to a much larger and more diverse scale. In addition to the organic block, he is responsible for more than 1,600 acres of conventional and sustainable wine grapes. His goal is to produce quality wine grapes under practices that are sustainable in terms of economics, environment, and social equity.
Right now, less than a third of the organic grape yield is made into their Naked-labeled wine, wine that comes from 100 percent organically grown grapes but has a small amount of sulfites added, and thus, cannot be labeled organic. The remaining grapes from the organic blocks are used in traditional Ste. Michelle wine products, according to style and flavor profiles. Although their organic wine production is not currently maximized, Way said they are in a position "to increase the organic wine volume overnight" if they wanted to.
There are obvious visual differences between their organic and conventional vineyards, Way noted. The organic vines usually look a little more ragged than conventional vines, with foliage typically showing some yellowing from leafhoppers, the major pest they must contend with. The canopy may be lighter in color, as well, and fruit set may be a little lighter.
But you’ll also find more insects and spiders, more weeds and flowering plants, and you will notice healthier soil under the organic vines, Way said.
Cropping levels tend to be slightly lower in the organic blocks, he said, adding that their average tonnage for Riesling at the Columbia Crest vineyard is around 5 to 6 tons per acres, compared to the organic Riesling that averages 4.5 to 5 tons per acre.
"Our goal is to make the highest quality wine product that we can and fit it into a sustainable program," he said, adding that some of the practices that work well in the organic blocks are being applied to their conventional vineyards.
Weed management is the biggest organic challenge, followed by leafhoppers, and mildew control in the variety-sensitive blocks.
Weeds are a bigger problem in the organic Riesling than some of the other varieties because more water is applied to avoid undue stress to the vines. Various weed control techniques have been tried in search of an inexpensive method, including steam machines to burn the weeds and using sheep to munch down the weeds in early spring. The sheep worked well, but the practice is dependent on neighboring crops (the sheep are not fenced in) and the amount of weed cover available. After using sheep the first year, organic peas were grown nearby the following year, and the sheep owner did not want the liability of errant sheep damaging the pea field.
For now, they use a cultivator under the vine rows four to five times a season to control weeds. They also hill or mound dirt over the weeds at the base of the vine to reduce weed pressure.
Herbicide use on conventional grapes has also changed due to their sustainable grape-growing efforts—use of residual herbicides like paraquat (Gramoxone) has almost been eliminated.
Sulfur and oils are used to help control mildew and are sprayed on a preventative schedule every 7 to 14 days. He noted that they go lightly on the sulfur to avoid mite flare-ups. "With Chardonnay, a variety susceptible to mildew, we learned that you have to go hard and be on the preventative side," Way said.
To control leafhoppers (the only troublesome insect they’ve had to worry about so far), they try to time mechanical leaf removal with leafhopper build-up to reduce the populations, although logistically that is difficult given the number of acres they farm.
"You have to adjust your tolerance levels for leafhoppers in the organic blocks," he said, adding that there is no silver bullet for pest control. "It takes a few years for the beneficials to build up. What you get the first few years are huge pest pressures that no amount of inputs used will alleviate the problems."
Neem oil is used when leafhopper populations exceed the economic thresholds, but it is only moderately effective, Way said. "We’ve learned you can live with more leafhoppers than we thought we could. They don’t need to be annihilated."
Ste. Michelle is applying some of the economic pest thresholds used in the organic blocks to its conventional grapes. "It’s not necessarily a bad thing to have the basal leaves dry up and fall off due to leafhoppers," Way said. "That’s just less leafing that you have to do. But you want the pest population numbers to be under the economic thresholds."
He noted that they haven’t had to spray for mites in any of the Columbia Crest vineyards in the last three years.