It’s early in the season, but it is already one for the books for wine grape grower Jon Ruel, chief operating officer for Trefethan Family Vineyards.

Located in the Oak Knoll District of Napa Valley, this has been the driest winter in more than 40 years. April was the warmest for degree-days in more than a decade. Also, this spring was one of the very few when Ruel didn’t have to get up in the dark morning hours to start frost protection measures.

Dry weather prompted him to begin irrigating his vines three months earlier than usual. Meanwhile, his field crews have been hard pressed to keep up with the task of thinning fast-growing vines of unwanted shoots.

However, he’s not complaining. His 2013 grape crop is off to a promising start. “The vines look fantastic,” says Ruel, who also serves as president of Napa Valley Grapegrowers.

“Overall, total rainfall since the last harvest wasn’t all that bad, it’s just that we got most of it in November and December,” he says. “That recharged the aquifer, but it didn’t provide much available moisture for the vines this spring. To make up for that, we began irrigating in March and April before bud break.”

His early varieties, including Chardonnay and Pinot Noir, began blooming in mid-April, about seven to 10 days earlier than average, He expects the bloom will be finished in his later varieties, like Cabernet Sauvignon and Petit Verdot, by early June.

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Growing conditions since bud break have been ideal. “The shoots have grown rapidly and, in terms of its effect on the set, the weather couldn’t have been better — sunny and warm,” Ruel says. “We’ve already started removing leaves and laterals to craft the light environment around the clusters. That should go quickly. With the drier soils, there shouldn’t be as much lateral growth as usual and the vines won't get as bushy.”

Normally, Ruel allows the cover crops in the vineyards, including clovers, barley and legumes like beans and peas, to continue growing through the spring. However, he disked them under much earlier than usual to preserve moisture for the vines.

The rapid growth of his vines this spring and the warm temperatures have combined to raise the powdery mildew pressure in the vineyards. As a result, Ruel has been keeping the intervals tight between fungicide sprays.

This season, he’ll continue monitoring his vineyards for the presence of any European grapevine moth. Napa County is one of six counties in the state that remain under EGVM quarantine restrictions. First discovered in California four years ago in Napa County, the population continues to decline as the industry gains the upper hand on this invasive pest.

Ruel will get an idea of crop size in mid-June ahead of thinning the clusters. Very dry springs like this one usually don’t equate to huge berries. “But, with smaller grapes, the flavors are more concentrated, and you can get some great wines,” he says.

This year’s early bloom likely portends an early harvest and a reduced threat of crop-damaging rain then. “That’s exciting,” Ruel says. “In the past few years, we’ve had some late harvests.”

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