It’s that time of year again — when we anxiously await the ripening of the grapes. More specifically, we are keeping an eye on the sugar content of the grapes versus the development of the flavors and tannins in the fruit. It never happens on any particular schedule and any of Mother Nature’s variations can set it off in any direction. A series of cooler than average days can suppress the sugar content and ripening. A heat wave can send the sugar content racing upward before the fruit has a chance to develop its full flavors.
If that description sounds in any way knowledgeable, don’t be fooled. I took exactly half a course in Viticulture at the feeder college to UC Davis, so I only know enough to be dangerous. However, at this stage, what is required is not knowledge but grunt work, and I am available, practiced and knowledgeable at that. More specifically, testing the BRIX — which is the sugar content of the grapes — involves walking every single row in the vineyard, picking one berry from each vine and testing the combined juices. The BRIX level shoots up as the day warms, but subsides as the evening cools. So the truest reading is in the early morning.
Dutifully, I was out in the vineyards a little after 8 with my marked Zip-Lok baggies. Since we have four different types of grapes, the goal is to pick a sample grape from every vine of each type in separate bags. Not too terrible a task for the upper vineyards which are flat and mostly Cabernet with a few rows of Cinsault. But the lower vineyards, where we have our Rhone varietals — Grenache and Mourvedre — was a bear. Especially since I hadn’t gotten the earliest of starts and it was starting to get hot. These are also the vineyards on the sloping side of our hillside. Picking “berries” here involved walking on an extreme slope, made more difficult by the damned ground squirrels who have been digging holes all through the vineyards. Clearly I didn’t get on the stick hiring Sonoma’s most fearsome rodent killer and — despite a heroic effort by our resident hawks — the little bastards are making vineyard travel extremely hazardous. It’s also prime season for Tarweed which coats anything it touches with a turpentine-like sap. Needless to say, I was covered by the end of my foray. If I can’t wash out the Tarweed, I may need to burn my clothes.
Oh, and once fire season is over, we need to get in here with flamethrowers and burn out the Star Thistle.
No doubt, walking the vineyard this way is a bit of a slog. But it’s a good way to get in touch with what’s happening at each vine. One thing I did notice was that, while our vines have been carefully pruned by our vineyard manager, some vines seem to have sprouted out like Audrey in Little Shop of Horrors. Our original vineyard manager, Clarence — who has since passed the business to his son and is currently re-engineering some of our water systems — has been passing on to me some of his fifty years of vineyard experience. He said, as of twenty years ago, vineyard people have noticed unusual green growth in vines. He’s convinced — and has good evidence for his hunch — that Chinese coal burning is putting massive amounts of nitrogen in the air and spurring unusual growth. In Clarence’s world, the Chinese have a lot to answer for!
Massive green growth is not a good thing. At this stage, you’d rather have the vine’s energy going into ripening grapes, not pushing through new greenery.
After bringing my baggies back to my sink, I crushed the berries in their bags and examined the juice through a Refractometer. As we had suspected, we have a few weeks to go before we reach picking ripeness — which can be anywhere from 25 to 28, depending on how alcoholic you want your wine to be. (The more sugar, the higher the alcohol as the yeasts eat sugar and excrete alcohol, eventually drinking themselves to death!) In recent years, we’ve been aiming for a more European style wine with a lower alcohol content, so we may pick at 24 BRIX. My readings gave me:
Cabernet, upper vineyard: 21.3
Cabernet, lower vineyard: 21.1
Mourvedre: 19 (always our late bloomer!)
If you expect about a point of BRIX rise per week, we’ll be picking in late September, barring a heat wave. But it’s been a relatively temperate summer with few days near 100 degrees. That’s all boding well for a long slow ripening where the fruit flavors keep pace with the optimal sugar content.
It could be a very good year.