(Wines&Vines) - Wine grape grower Jennifer Thomson ordered pruning of her family’s Napa vineyards in January. But driving through Napa’s back roads this weekend, the fourth-generation grower saw several unpruned grapevines showing signs of bud break.

Thomson’s family has farmed vineyards on the Napa side of the Carneros AVA since 1938, with a current total of 90 acres. The vines displaying bud break were not part of Thomson’s vineyards but on some nearby rolling hills. Choosing to keep its skilled crew of four working year-round, Thomson Vineyards started pruning during the record-dry month of January.

“We were among the first to do it in Carneros,” Thomson said. “Taking advantage of the dry period keeps disease pressure low.”

Buds are starting to push on a smattering of the yet-unpruned vines, she said. About 70% of the vines are already pruned. “We’ll begin working on the last 30% of pruning this week.”

Thomson kept her trained crew working through the winter with trellis amendments and cleaning up equipment barns disheveled by the August Napa earthquake. “We have to keep them working so they didn’t jump ship,” she said of the laborers.

With her longtime family background, Thomson watches other plants bloom: “Pears and plums come first. When you see acacias bloom, it’s panic mode: Finish pruning,” she explained.

Thomson noted that seeing bud break in late January is “stressful for growers, labor and vines.”

 Al Wagner, director of vineyard management at Napa’s 70,000-case Clos du Val commented, “The acacias are blooming.” Although he hasn’t noted significant bud break in the winery’s 300 acres of Napa County vineyards, he has seen a small amount of bud swell. “It’s safe to say bud break will be in about two weeks,” Wagner predicted.

About 75% of Clos du Val’s vineyards already have been pruned, starting in early January, and Wagner predicted that pruning would be complete in 10-14 days. He’s not worried about post-pruning damage, saying, “We spray with fungicide for Eutypa, right behind pruning. This has given us good success for six or seven years.”

Francisco Araujo, senior viticulturist for Atlas Vineyard Management, which farms approximately 1,000 acres in California’s North Coast, Santa Barbara County and Oregon’s Willamette Valley, commented that 2015 is shaping up as an early growing season. “There is not yet generalized bud break, but growers are seeing signs of an early onset, especially in vineyards where soil is shallower and the vines are weaker.” For growers who have pre-pruned, “It’s not a big deal,” he said.

 Atlas started pruning in Sonoma County in January, and its vineyards are “probably about 40% pruned.” He expects pruning to last another month, until early March.

 “If we started pruning in December, we’d have to protect the cuts with fungicide. It’s ideal to prune in late January or February,” Araujo said. “When the wounds start bleeding, the natural sap means the vine is already active.”