Finally the rain stopped and we’re all coming out of hiding. In thirteen years living here, never before was my seasonal creek running at the end of June! If 2010 was the year of raisining, with killer late-season heat waves… 2o11 looks to be quite shattering. Doug Hill of Oak Knoll Farming told me reports are 50% average shatter on Cabernet Sauvignon throughout the valley. A local vineyard appraiser and banker quoted the same statistic. My vineyards are 20-30% shattered on the cab franc and merlot.
What am I talking about?
“Shatter” is the result of cool weather preventing all the potential berries from forming on the grape clusters. During the critical Spring flowering season, if temps are too cool, the pollination cycle doesn’t finish and all those little flowers just fall off. And that’s that. Open, lighter clusters.
Doug, our 3rd generation farmer who has seen it all and generously answers all my questions, showed me how he evaluates shatter on a merlot vine in Oak Knoll near his office. You lay a cluster in the palm of your hand, then tap the top of it with your other hand. You won’t knock off any berries that wouldn’t fall off on their own, so you don’t have to feel like you’re causing any trouble. A good breeze, rain, or time would have the same effect. Developed berries don’t come off. If you get little brown flower caps in your hand, no problem, but small green balls…. that is 2011 wine that will never be.
Shatter is not the end of the world, it just means fewer berries on the cluster. In fact, a nicely-aerated cluster–like the one above–might just allow us to “drop” less fruit later in the season and maintain a balanced vine yield. Open clusters won’t stay wet and get moldy in a light rain. All good.
The conditions that bring shatter have a more challenging sister issue. With fluctuating periods of warm and cool temps in Spring, we get the dreaded “uneven set.” Perhaps half the cluster goes through pollination in a warm week, then it cools down and the other half develops maybe two weeks later.
Now you’ve got what the farmers call “hens and chicks.” Smaller berries ripening well behind the first group.
This is a challenge. You want pick the cluster–for that matter, the vine and the block–all at once, so you’d like one of two things to happen–the smaller berries to stay green and tiny (“shot-berries”) and either stick on the stems going through the de-stemmer, or fall through the sieve on your shaker table at the winery, so only the lovely ripe berries go into the fermentation tank. Or you’d like a balance of ripeness between the two stages that creates a nice complexity in the wine.
We’ll see how it goes. Each year, nature gives us new challenges. Only a glutton for humility could love this business!