Are You Ready?
Determining Harvest Readiness in Wine Grapes at Unionville
I am packing up and getting ready to escape the office for a great yoga class. I’ve been looking forward to the class since Monday.
It’s only Wednesday. Hump Day. The Wednesday before our Annual Fall Harvest Festival. There is plenty to do - 5 pm and the vineyard crew is just starting to press the Riesling grapes they’d been harvesting all day.
So...close... I’ve got my yoga mat in my car. I’m ready to go. I’m almost there...
And Cam stops me.
Dang. So close.
“Wanna go sample grapes?”
He’s got his vineyard hat on, and his dog Rocky is at his heels. There is really no way I can say no.
Such a beautiful afternoon. A bit warm, but comfortable. I love fall. The leaves are changing color, and it’s so quiet and peaceful out here I easily forget I’m in New Jersey.
We walk through a break in the treeline, up the hill, to our Top Vineyard. The Riesling and Chardonnay have all been picked, though there are some now-very-sweet grapes still hanging on the vines.
We continue, back to the red grapes. Back here, thanks to New Jersey Agricultural Extension and Rutgers University, we have a new weather station. The station sends data to NEWA, the Network for Environment and Weather Applications, housed at Cornell Universty. Cornell and Rutgers University scientists explore the data and use patterns to advise growers like us on when to expect diseases and insects. As growers, we use the scientists’ research results and our very own vineyard data to help manage pests and also to predict growth and maturation during the growing season. The more we know, the better farmers we are.
Moving towards the grapes, we begin to take samples. Taste, you know, is of primary importance! These grapes are just delicious.
The main reason we are up here is to take samples of the Cabernet Sauvignon and of the Chambourcin. Cam hands me a ziploc bag and sets down some ground rules
- Never sample the last two vines in the row. They do not face the same competition for soil moisture and nutrients that most vines in the row face.
- Take samples blindly. We “cherry” pick when we look (no pun intended). Try and take grapes from the shoulder and from the bottom of the cluster.
- Zig zag. Take some grapes from the row on your left, then the row on your right, and back and forth down the row.
Then, he sends me off.
Well, now! This seems to me to be quite a big responsibility. He’s going to use my sample to determine whether or not to harvest and to see how far along these grapes are.
Pretty big deal.
I walk down rows of Cabernet and he takes Chambourcin.
We meet at the end.
“Did I not get enough?” We each half-filled our Ziploc baggies, but he’s also holding a cluster of dark, plump Chambourcin grapes.
“My daughter loves these.”
Fair enough.
The Chambourcin grapes, compared to the Cabernet, are huge, nearly double the size, and 
very very red.
We walk down the hill, Cam’s dog running out ahead, and bring the samples back to the lab.
There, we “smoosh” the grapes (smoosh is a technical term, you see). Cam measures the sugars and acidity for each juice. He doesn’t tell me anything. Not before I taste.
I taste the two juices, almost like I would taste wine, noting the flavors and where on the palette I taste them. The Cabernet has great blueberry notes, with a bit of green apple tartness. The Chambourcin starts off blueberry - then, bam!, overwhelmingly green apple.
The big reveal: The acidity of the Chambourcin juice is much higher than that of the Cabernet, and neither is ready to be harvested.
The tastes of the grapes and of the juice tell Cam everything. The numbers he gets from the lab tests only back up what he knows from tasting alone.
I miss my yoga class. I’ll make it to another one. Harvest is just a crazy wonderful time of year. I don’t want to miss it.
~Stacy, Operations Coordinator & Wine Geek
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Also in Unionville Grapevine
The Best Wines are the Ones You Fight For
We picked from 5am that day until a little past midnight, almost 19 hours of harvesting. The pick was only interrupted for bathroom breaks, pizza, and eventually some beers to keep morale high. I think the high morale beer was Miller High Life, although the details are fuzzy and it would only have been selected ironically. It was the most tenacious day I can recall in the field here. We picked nearly 10 tons from three different vineyards, finishing with the Pheasant Hill Chardonnay. We saran wrapped the bins during transport and weighing back at the winery as Ophelia's first raindrops splashed down just after midnight.
Too Frigid For May: How Unionville Reacted to Destructive Frost
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