What the French call rain, grape growers in Napa and Sonoma call irrigation. The ability to dose water to vines under strict management is a godsend to grape growers. Drip irrigation is an expensive prospect when you think about it. For example, Larkmead has 113 acres under vine, with roughly 1,000 vines per acre. That's 113,000 vines that require the pictured irrigation system installed. But this system pays dividends. It allows us the ability to put as little or as much water at will. A typical irrigation schedule can call for four, six, eight or more gallons of water per vine throughout different points of the growing season. With this type of control, we can also add nutrients to the vines during the irrigation process. This is an efficient and effective method in managing the vine's growth and development. During the current heat wave(s) we've tried to beat the heat by irrigating to hydrate the vines so they can cope with the pounding intensity of repeated hundred degree days. One gallon takes about one hour to ‘drip.' So, in order, to irrigate the whole vineyard, and monitor what gets what, it will take us up to four days working around the clock, turning water pumps and valves on and off. Our vineyard team has done a fantastic job in managing this process and our vineyard has been holding up very well during this period and not building sugars too fast. That brings me to sampling.
One of the 'sweetest' things we do in preparation for harvest is sampling our grapes out in the vineyard. Everyone will say this is the deciding factor of great winemaking - knowing when the fruit is ready. Adam Lee of Siduri has been blogging about this on the Wine Spectator website with a cast of winemaking characters from all over the world talking about the 2008 harvest.
But as we know, to each his own. Some people prefer tart acidity over no acidity; bitter tannins before soft, supple ones; subtle fruit instead of jammy explosions in your mouth. You can definitely make wines of each of these styles by picking your grapes on the same day (the science, I mean art, of winemaking), but if you know what you are looking to create before getting your boots dirty in the vineyard, you'll have a better understanding of when the grapes are ready to achieve your particular style of wine.
So what has the heat wave been doing to the vines? It is causing sugars to rise in the grapes at an unbalanced rate with the rest of the fruit's maturity. When this happens and there is no weather relief in sight, you are stuck with wine grapes that are essentially flavorless behind an overbearing ‘sweetness.' High sugars equate to high alcohols and very front-end loaded, one-dimensional wines.
During this period we have been sampling the grapes repeatedly to monitor their ripeness, checking sugar and acid levels, canopy health, skin and seed maturity.
When walking the vineyard, the first thing you will notice is canopy health. Are the leaves remaining green, getting dull or yellowing? Vines will start yellowing around the fruit zone which means they are telling you they are working overtime and they don't have much more to give to the development of the fruit.
When you pluck a berry from a cluster of grapes and put it your mouth, the first thing you feel is the texture of the skins followed by the juice explosion. As you mash the grape around your mouth, is the juice too sweet, or just right? Are the skins chewy and creamy or dusty and papery? Are the seeds pliable or crunchy? You'll spit the remains in your hand, check out the skins and look at the seeds, are they green, are they still smothered in pulp? These are all indicators for grape maturation. But one grape does not make a wine. So, we sample whole clusters, randomly throughout the specific part of the vineyard we designate. We'll bring the clusters back to the winery and crush them by hand and let the juice macerate on the skins for up to five hours. We'll then decant the juice and check the color. Mature skins will create darker, richer hues after maturation and this is one more determining factor in how and when we know the grapes are ready.
The juice macerates on its skin, which we will leave for up to five hours before decanting the juice and measuring its sugar and acid levels. We'll check the color and taste. And then we'll decide when to harvest. Typically we'll sample a vineyard block in this fashion about three times. But that doesn't include the number of times that we'll walk the vineyard tasting and formulating our readiness decision. This particular parcel of Cabernet will be harvested next week. I'll keep you posted on how it turns out.
Larkmead Vineyards in Napa Valley. Dan has an MBA from New York University and worked as an Ad Exec in New York for several years, before switching it up and trading his suit for a move out west.