Grape Growers Excited About Chilly Temps

While many Bay Area residents bemoan this week's cold temperatures, grape growers in the wine country are heralding the cold snap as good news for spring crops.

This week's chill helps send the vines in the famed wine region into "a good state of dormancy," said Bill Hanna, a member of the Napa Valley Grapegrowers board and a fifth-generation California grape grower.

It can also help kill some winter insects, he said.

Low temperatures and frost become a concern in the spring, as sap starts moving up the vine and the vines start budding, he said.

"Before that, having the cold weather is good," he said. Hanna estimated that local grapevines can survive temperatures down to 10 or 12 degrees.

Much as homeowners worry about frozen and burst pipes in cold temperatures, Hanna said he spent much of Monday making sure his irrigation lines were drained.

Last week the Napa Valley saw some 27-degree mornings, Hanna said, "which pretty much took care of anything that still had some green in the leaves."

Nick Frey, president of the Sonoma County Winegrape Commission, agreed that the cold can actually help next spring's crop of grapes.

"This freeze puts an end to the season," he said. "It bodes well if you have good dormancy, you get a more uniform bud break in the spring."

Harvesting is easier for growers if buds emerge at the same time, rather than over a two-week period, Frey said. Pruning is also more effective when vines are dormant, he said.

The cold temperatures are expected to linger through one more night, according to the National Weather Service. A freeze warning and frost advisory have been issued throughout the Bay Area from midnight through 9 a.m. Wednesday.

"Now we've got the cold; we're still waiting for the rain," Frey said.