Napa,Calif. -- It’s been a nail-biter of a year for California Coastal grapegrowers, but it will be all over before the rains forecast for the coming weekend.

On Monday, Randy Ullom, winemaster for Sonoma County-based Kendall-Jackson Winery (4 million cases), said, “We’re not done yet,” but expected to complete picking this week, particularly with warm sunny days on tap.

He reported that still-to-be picked varieties include Viognier and Syrah in Santa Barbara. “They look spectacular,” he said. Likewise, some Chardonnay and Riesling are still out in Monterey County, and the weather has been great. Ullom noted that Monterey largely missed the recent heavy rainfall.

On the North Coast, K-J is waiting on Viognier, Chardonnay, and of course a lot of reds including Cabernet Sauvignon. “They’re in good shape; it’s some of the best Cab I’ve ever seen,” he said.

Ullom reported that crews encountered Botrytis in some areas, but surprisingly, less than last year. “It’s like a year in France,” he said. Pinot came in before the rain and was no challenge.

Ullom also noted that Brix levels have been low on the Bordeaux varieties. “They grew through their green flavors and developed ripeness at a little lower sugar than usual. They’ll be a little lower in alcohol and should be very elegant.”

At 1.5 million-case Gallo Family Vineyards, Healdsburg, Jim Collins, director of vineyard management, reported: “We are still picking grapes. 2010 is definitely a vintage that presented some tough challenges, but the overall quality of the grapes has been outstanding. The wines in the tank and barrels reflect this as well. The grapes were allowed to develop incredible flavors with the extended hang time. The recent rain made things more difficult, but we are able to keep moving forward with harvest. The Cabernet Sauvignon that is still on the vine appears to have weathered the storm well. My best estimation is that we will wrap up harvest by the end of next week.”

Central Coast
Further south, Clay Brock, director of winemaking at 150,000-case Wild Horse Winery & Vineyard, Templeton, noted that during the past few weeks, Mother Nature challenged the Central Coast with ever-changing weather conditions.

“Two weeks ago, Paso Robles did not disappoint, displaying its signature daily temperature fluctuations that make it the perfect climate for flavor development. After nearly a week of temperatures in the 90°s during the day, followed by cool 40°F nights, all of our Paso Robles Cabernet Sauvignon and Merlot has been harvested, and fermentation is nearly complete. The extraction shown in these varietals is deep, dark, and the color is just exactly what we’re looking for.”

He added that recent unseasonably cool and overcast weather with a small amount of rain followed by thundershowers pushed his team into bringing in more fruit; they were able to bring in the majority of it before the storm. “100% of our Chardonnay has also been harvested, and we look forward to bringing in some more of the aromatic whites as our grand finale.”

Napa virtually complete
In Napa Valley, a Pacific storm system brought anywhere from 1-5 inches of rain to the Napa Valley floor, and even more in some higher elevation areas throughout the region. Working literally around the clock, winegrowers raced to get the final push of grapes to the wineries. Most vintners are reporting as of this week that their grape deliveries are complete.

Some hillside districts, which account for a fraction of the region's overall production, are bringing in their final tonnage.

"Interestingly, we were in almost the similar pattern as 2007 and 2009 at harvest: heavy rains when the last of the hillside districts had some fruit remaining. We survived to make spectacular wines. There is a lot of Armageddon-like chatter out there, but still, from every winemaker I've spoken with, everyone is delighted with what they are tasting in these young wines all across the board," said Bruce Cakebread of 150,000-case Cakebread Cellars, whose family has a 38-year history in winegrowing in the Napa Valley.

Tom Ferrell, executive director of the Spring Mountain Appellation said, "Given that we're up on Spring Mountain, the rain we received last week was quick to run off, and our grapes, smaller and tougher than those on the valley floor, stand up well to inclement weather. I've spoken with member wineries throughout the district, and am hearing that winemakers are really encouraged about this vintage and excited about what they have in their tanks. Those still with grapes hanging are getting very close to picking."

David Beckstoffer, president of the Napa Valley Grapegrowers and of his family’s vineyard company, reported that Beckstoffer will finish picking this week in Napa, as well as in their properties in Mendocino and in Lake County’s Red Hills. The Red Hills are the latest, but most of the crop there is machine harvested, so comes in quickly.

He confirmed that the vast majority of Napa growers will be finished this week.

Peter Richmond of Silverado Farming, which manages multiple properties in Napa and elsewhere, said that Silverado got almost everything off before the recent big rain. “The earlier rain didn’t affect anything much.” He does have six tons to come in on Spring Mountain, and they will be in this week.

Richmond also reported that overall yields are down significantly this year, particularly for Bordeaux varieties like Petite Verdot and Cabernet Franc. He admitted that he’s not ready to call the quality yet. “Let’s wait until February. It’s too early to tell,” he said.

QUICK GLANCE OF THE 2010 GROWING SEASON

	Max Temperatures	Precipitation	Degree Days
March	Normal	Below Average	50-100 below normal
April	Below normal	Above Average	80-180 below normal
May	Below normal	Above Average	130-160 below normal
June	Normal	Below Average	Near normal
July	Below normal	None	60-100 below normal
August	Below normal	None	60-100 below normal
September	Above normal	Below Average	Near normal
October	Below normal	Above Average	30-70 below normal

Source: Erik Moldstad, Precision Forecasting LLC

Vine water use
An interesting look at the year comes from Thibaut Scholasch, Ph.D., founder of Fruition Sciences. Those results are based on vine water use measurements using sap flow in Napa Valley.

Overall, the late season start, combined with the high soil moisture availability, maintained a high level of water supply to the vine until later in the season (i.e. veraison). This caused the level of vine water use to be high compared to previous years. The consequences of that are:

a) Delayed maturation;
b) Larger berry size.

Growing degree-days (GDD) is a climatic measurement that scientists use to estimate the “speed” at which the plant develops its leaf area. The faster GDD accumulates, the earlier the plant reaches its full size and depletes the soil of its water. In 2010 GDD accumulated more slowly than usual (see graph).

In this cool climatic context, vineyards were “trained” for a slower growing rate and very slow maturation profile. The intensity of the heat waves (end of August to mid-September), combined with this climatic context, put vineyards under greater pressure, causing a lot of sudden berry dehydration. As a consequence of berries losing water, sugar concentration suddenly increased, but this sugar increase was not related to polyphenols and aroma maturation.

Despite high sugar level, the maturation profile was a slow one, decoupling sugar accumulation from skin and seed maturation. This should result in wines showing more dried fruits-like aromas, less color intensity and less concentration.

Scholasch will detail terroir-specific variations from this general trend during his vintage report on Nov. 30 in Napa. Visit fruitionsciences.com for details.