Author’s note: After I wrote this column for The Washington Post about how local vintners were anxious about the early spring weather, but before it was published, warnings went out about a potential killer frost last weekend along the Piedmont Mountains. There were fears of a repeat of 2007, when the “Easter Massacre” of late April decimated early budding white grapes from Missouri throughout the southeast, as far north as Charlottesville. Vintners were advised to reserve helicopters and work crews to guard against frost. Luckily, the weather continued to warm and there were no reports of frost. Vintners in Maryland and Virginia may not have totally uncrossed their fingers yet, but this week’s balmy temperatures probably have them hoping for rain more than anything else.
With the threat of frost over, at least for the time being, Christine Vrooman resumed “debudding” her vines at Ankida Ridge Vineyards, near Amherst, Va. Christine, who kindly offered the photo here of her budding pinot noir vines, explained that debudding is an early form of yield control. By removing excess buds, she can control vigor and coax the vines to channel their energy into a limited number of grape bunches. When the frost alerts were posted, however, she held off – if frost were to kill some open buds, survivors could still produce a crop. That’s part of the delicate balance local vintners walk as they try to coax optimum ripeness and quality from their grapes in this tricky Eastern climate.
“Now is the time we wait, and fear,” said Claude DelFosse, of DelFosse Vineyards in Faber, Virginia, about 20 miles south of Charlottesville. It was a pessimistic statement for someone whose 2007 Meritage red blend had recently been selected into the “Governor’s Case” of the 12 best wines in Virginia. He was referring to “budbreak,” when the first buds appear on the newly pruned vine shoots, signaling the start of the growing season. This happened around March 25 for DelFosse, about two weeks earlier than usual. New vine shoots are especially vulnerable to frost, and the frost season in the Piedmont region lasts until mid-May, so an early budbreak means vines are at risk for a longer period.
“Freezing temperatures of about 28 degrees, especially with heavy dew, can nuke a vintage in the bud,” says Lucie Morton, a vineyard consultant to several wineries in the mid-Atlantic and California.
Frost protection in vineyards can be very elaborate, and very desperate. Windmills help move the air around, and in extreme cases wineries even hire helicopters to hover over the vineyards to keep air circulating with their rotors. That’s one reason growers favor higher ground with steep slopes – the elevation provides “air drainage” in springtime as the cold air flows downhill, away from the vines. Next time you visit California wine country, notice how the windmills are always in flat vineyards.
Weather is forever on the minds of vintners from budbreak through harvest.
White grapes tend to bud earlier, so their risk is greater. Reds, especially cabernet sauvignon, break later – this means they may survive a late spring frost, but they also ripen later and are more susceptible to fall rains, including tropical storms and hurricanes. In 2011, local harvests of white grapes began just before Hurricane Irene swept up the coast, and generally finished in the mild weather that followed. Reds were caught up in the September deluge that followed the arrival of Tropical Storm Lee.
There are other hazards too. Cutworms and flea beetles worry Jeff White of Glen Manor Vineyards, winner of this year’s Governor’s Cup for his 2008 Hodder Hill red blend. “One concern is warm weather causing buds to swell and then cool weather keeping them from opening and advancing leaf and shoot growth,” making the buds vulnerable to the insects, he explains.
The bugs’ effect at this early stage can be devastating. “One mini-munch of a bud is like a scissor cut in folded paper,” Morton explains. “Lots of holes in leaves and teeny grape clusters.”
While this is the earliest budbreak in memory for many local vintners, it follows a pattern over the last decade, says Tony K. Wolf, professor of viticulture at Virginia Tech, who maintains an experimental vineyard near Winchester. “Our normal bud break for chardonnay has advanced from around April 21 in the early 1990s to around April 7, on average over the last five years,” Wolf says. “The longer season does not really benefit us – the downside is a longer period in which grapes are at risk of insects and fungi for which the growers must provide protection.”
Two years ago, this region experienced its earliest harvest ever, as the hot summer temperatures pushed grape sugar levels to ripeness in mid-August. Startled winemakers scrambled to pull the grapes before they turned to raisins. Last year was a scorcher too, until it rained for 30 days during harvest. That’s why no winegrower will make a prediction – at least not an optimistic one – about this year’s vintage until the last grapes are in the winery.
For us consumers, vintage variation is part of what makes wine so fascinating. For vintners, it’s simply nerve-wracking.
“In early spring grape growers and their consultants take it one degree at a time, and in early fall we take it one day at a time,” Morton says.
Published in The Washington Post on April 11, 2012.