We’ve already harvested much of the Chardonnay and Pinot Noir growing at vineyards we manage in California’s North Coast. But how do we know when to harvest?
As the in-house winemaker for Atlas Vineyard Management and our Northern California regional manager, Anthony Weytjens works directly with clients talking about the optimal time to pick. For larger sites and wineries with multiple vineyards, Anthony likes to experiment with picking one site on the early side, to give the resulting wine some acidity and backbone, while letting other sites ripen more, adding nice developed flavors.
Brix (sugar) levels, acidity and pH are all measured regularly at sites managed by Atlas. For grapes that will undergo malolactic fermentation, http://www.bcawa.ca/winemaking/ml.htm such as buttery Chardonnays and many red wines, Atlas can test for levels of malic acid. When it comes to making the final decision about harvest date, however, Anthony says tasting the berries in the vineyard is the real test.
Anthony describes Chardonnay as a somewhat neutral grape in terms of aromas, so mostly he’s looking for nice acidity and balance as indicators that picking time is approaching. He looks at the seeds to see if they’ve turned brown, an indicator that they are reaching a level of maturity to lend nice tannins to the juice. Harvesting while before the seeds are ripe can create undesirable green tanins.
Unlike Chardonnay, aromas are an important part of deciding when to harvest Pinot Noir. The skins begin to soften when this grape nears maturity, and balanced mouthfeel is important. When evaluating juice during the days leading up to harvest, Atlas vineyard managers are looking for floral and fruity characteristics.
Variety in picking decisions
Some Atlas clients opt to pick Chardonnay and Pinot Noir early in the harvest season. Typically these grapes are destined for low-alcohol, elegant wines. Other wineries opt to let the fruit hang longer and develop higher sugar levels, which leads to higher alcohol levels. These grapes tend to create bigger, more structured wines.
“You have those four or five days of perfect ripening for a great wine,” Anthony says. “It really depends on when winemakers think is the perfect moment to pick.”
Chardonnay and Pinot Noir are two of the three grapes most commonly used in sparkling wines (the third is Pinot Meunier). Although the grape varieties are the same, the traits desired and the resulting harvest dates are very different. Sparkling winemakers are looking for higher acidity and lower sugars, so they pick Chardonnay and Pinot Noir weeks earlier than other winemakers would consider harvesting those varieties for table wines. At that stage, Anthony says, the aromas are completely different; green bell pepper is a common characteristic at this time.
Haste makes waste
Picking too early can lead to wine with green characteristics such as vegetal and herbal flavors and aromas. Anthony says some people can call a pick when they are pleased with the sugar, acid and pH levels in the vineyard, only to find that the numbers don’t match when the grapes come in — a real problem since grape clusters are not like stockings you can re-hang from the mantle. A common culprit behind this blunder, Anthony says, is exclusively sampling berries on the external, sun-facing side of the cluster. These berries have higher sugar levels and more developed flavors. For a more accurate reading pick berries from the center of the cluster or use whole-cluster sampling.
The weatherman is your friend
Of course waiting too long to pick leads to a different set of problems, such as lychee flavors for Chardonnay and prune-like qualities for Pinot Noir. A simple solution to this problem is to watch the weather forecast religiously during harvest season. A couple of days of hot weather can send sugar levels soaring.
“Two days of 100°-plus weather can mean going from the perfect moment to harvest to being completely over-ripe and missing that window of picking,” Anthony says.
And when it comes to rain, Anthony says it’s better to pick a block just before the rain than to let it hang through a storm and risk waiting for Brix to climb back up. The decision to wait to pick until after a storm could come with a side effect of Botrytis development on the grapes.
Making the right call
Ultimately, Anthony believes that when to pick is the most important issue growers and winemakers decide when it comes to making good wine. Good thing the Anthony and the AtlasVM team is here to help make the call.