The Fizz #2: Napa Valley's unique terroir, with legendary winemaker Cathy Corison
In this interview, Cathy Corison and I talk through Napa Valley terroir, the details of canopy management, her approach to harvest dates, and more.
For the Fizz episode 2, I sat down over Zoom with a wine legend, and a personal hero to me—Cathy Corison of Corison Winery in Napa Valley. Cathy has been making wine in the Napa Valley since 1978, after graduating from the University California at Davis with a masters in enology. In 1987, after making wine for several different Napa-area wineries, she started Corison Winery where she makes terroir-driven Cabernet Sauvignon that focuses on elegance and sense of place. Cathy has been a mentor to countless people, is known to be a teacher, a dedicated farmer, and a champion for women in winemaking. I was thrilled that she agreed to speak with me and give me a peek into her farming and winemaking style.
On Zoom, Cathy is immediately ready to go. She’s clear and concise in her responses, and speaks with incredible patience. Her drive and passion for her craft is evident as she talks about her winemaking process. Truthfully, I’m a little nervous to talk to someone I’ve looked up to for quite a long time. Cathy’s determination shines through this interview, where we go into the nitty gritty of Napa Valley terroir, the technical details of canopy management and harvest criteria, and Cathy’s role as a pioneer for women in the winemaking field.
Margot: Cabernet Sauvignon has a deep link to terroir in Napa Valley. What about that history is exciting for you?
Cathy: Napa Valley is really pertinent for Cabernet Sauvignon because I believe we can make Cabernet as well or better than any place in the world. I’ve always said that, and now I think most people in the wine world would agree. That’s because of the confluence of the amazing soils for Cabernet here, and the climate. Cabernet is a late ripening variety—it takes a lot of heat to get ripe. There are a lot of hot places in the world, but there are very few that also have a tremendous diurnal shift in temperatures. We have hot days in the summer and into the fall, but we have cool to cold nights.
The fog comes in through the San Francisco Bay and right up in to the Napa Valley, which is geologically an extension of the San Francisco Bay—it comes in every single night, almost. The temperatures plummet from the 90s down into the 50s and sometimes into the 40s every night. There are very few places in the world with that amazing diurnal shift. We have the heat during the day that gets Cabernet Sauvignon ripe, there are a lot of places that can’t rely on that. Even Bordeaux historically couldn’t get Cabernet ripe every year. We also have the cold nights that promote inky color and slow down the degradation of acidity, so we have really good natural acidity, which promotes complex flavors. Those are all the sorts of things we want to make a world class wine.
M: I know that you prefer the longer cooler seasons for your Cabernets. Now that climate change is presenting warmer, how will you navigate that change?
C: It’s complicated. We don’t really know what to expect. In the last nine years we’ve had the hottest season ever recorded in Napa Valley, but we also had the coldest season ever recorded in 2011. The warmest season with the biggest and longest heat spell was in 2017. What we’re seeing is a real roller coaster. We’re lucky that Cabernet is a very late ripening variety that takes a lot of heat to get ripe. As long as the nights keep cool, as long as that fog keeps rolling in every night, we’ll be making world class Cabernet Sauvignon. The expectations from all the climatologists is that the nights will remain cold, at least in the near term.
I have a tendency to wait and watch what people do. The strategies that people are using [to mitigate climate change] include shade cloth, like you’ve seen in nurseries. I’ve seen green, black, white, on the morning sun side, on the afternoon sun side. Nobody understands whether it works yet, but it may be a powerful tool. People are talking about micro-misting as well. There are winemakers already starting to experiment with varieties that are even later ripening than Cabernet Sauvignon.
We’re very careful with trellising. Many years ago, viticulturists would go to France and come back with a beret on their head and do exactly what they did in Bordeaux, and that usually meant strict vertical trellising, which exposes the grapes to a lot of sun and heat. Almost nobody is doing strict vertical trellising anymore, and I never have. I never liked it. With our canopy management, we can ensure our grapes get enough light and air—not too much, but enough to develop the flavors we want, and to lignify the seeds, which makes the tannins very velvety.
M: Can you talk about your approach to canopy management?
C: Grape growing boils down to balancing the way a shoot grows, the vigor, and how much fruit it has to ripen. That’s the first thing we control. I drop all third clusters. I’ve never met a third cluster on a shoot that I like, and it’s because it flowers later and sets later. Even if the crop’s not too big, it doesn’t ripen with the first two clusters. Some years there are a lot of them, other years there aren’t. Then we go through probably ten times.
One of the earliest passes is what we call suckering. Grape vines evolved to grow up in trees. They want to grow way more than we want them to. We hack them back so we can work them. Every year when the vines bud out, they push lots of shoots in places we don’t want them—on the trunks, in the heads, all over. One of our first passes is to remove all the suckers—those turn into shade later where we don’t want it. Then we go through once we have flowering and set. I don’t remove any leaves, but in the fruit zone on the morning sun side, I remove all laterals, which are shoots that grow after the primary shoot, and that will often have second crop.
Then in another pass, on the afternoon sun side, which is much harsher, because that’s when it’s so hot. There I’m removing laterals—we want dappled light into the clusters, but we don’t want so much that they get sunburned. Later in the season, the other really important pass is at veraison, when the green hard little berries are turning black and soft. That’s the only time we can see unevenness in ripening. It has nothing to do with the crop size—it has everything to do with evenness of ripening. When the grapes have mostly gone black, we drop anything that’s still green. Those are some of the passes we take every year.
M: The decision on when to start harvesting is such an important one. How do you know when the right time to pick is?
C: It’s experience. Every year I probably add another thing I’m looking at. I probably look at 20 different things. I walk the vineyards every day. Here in California it’s hot. We can shrivel up to any old sugar we want, but that’s not real ripening. I’m very concerned in watching the status of the vines because if they’re healthy and working, they’re ripening the fruit. I look at the sugar, the acidity, how the seeds are lignifying—they’re turning from soft and bitter and astringent to woody. When that happens, the tannins are much softer. I’m looking at how the whole berry colors all the way to the pedicel. I’m looking at how the skin releases from the pulp as the grapes get ripe. I’m tasting for the quality of the tannins, the flavor, the balance. The definition of a great vintage is when all of those things I want converge at the same place at the same time. It’s my most important decision every year.
M: Your Kronos vineyard has vines that are now 50 years old.
C: [laughs] This year! It’s such a gift as a winemaker to have these old vines. Here in California we had phylloxera come through again in the 90s and almost the entire North Coast had to be replanted because it was on the AXR-1 rootstock [which was susceptible to phylloxera]. Kronos fell through the cracks. It was on St. George rootstock planted in 1971, so it’s turning 50 years old this year.
[An aside: phylloxera is often talked about as a thing of the past, but the louse is very much present even today. California, Oregon, and Washington have been encountering phylloxera eating at own-rooted vines, or on vines planted on the AXR-1 rootstock. Learn more about phylloxera and its dangers here, and about new phylloxera biotypes here.]
M: What is it like watching those vines mature?
C: Those gnarly old ladies are so wise. We talked about heat spikes—they just sail through heat spikes like young vineyards simply don’t. They have much more resilience. Heat spikes aren’t good for flavor because sugar accumulates faster than all the other things that go on. If the grape vine is resilient and doesn’t suffer during a heat spike, it’ll be better for the health of the vine and for the flavors. The colder the nights are, the more color is produced and the more acidity remains. Those cool nights promote complex, inky grapes with great natural acidity.
M: What does it mean for you to make a wine with age-ability? How do you approach that?
C: It’s all about the way it’s built. Age-ability is mostly about the acid structure. The better the natural acidity, the longer lived it’s going to be. The phenolics are important too—the tannins and the pigments are very powerful anti-oxidants. They slow down aging. I knew before I ever started this project 34 years ago that these wines could belong lived. I knew the wines that have been made here since the late 19th century, Cabernet based wines, were winning expositions in Europe. We have a very long history of long-lived age worthy Cabernet Sauvignon, especially from what has been historically called the Rutherford Bench, which is where I grow my grapes.
M: American wine history to me is just so fascinating.
C: It’s longer than anybody knows! It goes way back. But then Prohibition, two World Wars and the Depression wiped out our industry. It didn’t start climbing back until the ‘60s.
M: Can you give me a sense of what has changed in Napa Valley since you started?
C: I moved here in June of 1975, two days out of college, and in less than a year the Paris Tasting happened. That catapulted us onto the world stage in a way that nobody could have expected, and it was kind of dumb luck. We’ve been hanging on for dear life ever since. It’s been a ride. It’s been thrilling to have a front row seat and watch it happen. When I got here, we were still trying to emerge from Prohibition which ended in 1933. Today, we’re considered one of the best wine growing regions in the world.
M: In your interview with Levi Dalton, you spoke briefly about blind tasting—you taste wines blind fairly often.
C: Every day!
M: Can you tell me why that’s helpful for you?
C: Anybody that tastes a lot knows how affected we are by what we expect to taste when we know what we’re tasting—that can be the house, or the price of the wine, etc. Nobody is immune to that. I taste blind because I don’t want to be prejudiced by what I know about the wine. I taste in several groups and we always taste blind. My husband pulls a wine blind for me every single night. It’s made me a much better taster over the years—that’s been going on for over 30 years. When it’s time to blend, I always taste all of the lots blind first. They’re set up for me so I don’t know what they are. It’s just the only way to not be influenced by your preconceptions. It’s really important. How many times have you tasted a $100 wine that you didn’t really like? How many times have you tasted a $20 wine that knocked your socks off? It’s better not to know so you can be much more honest with yourself.
M: Can you talk about your approach to blending? How do you know what you’re looking for? How do you know what that final wine should look like?
C: This wine was fully formed in my head before I ever started this project. I wanted to make a Cabernet that is powerful and elegant. Cabernets can be powerful no matter what you do, but it’s way more interesting at the intersection of elegance, for me. I knew I had to come to the Rutherford Bench to make this wine. It speaks of place and time, it graces the table—it’s built to make food taste better, and it’s also intended to have a long interesting life.
First, I taste all the components. I closely control all of the blocks that I pick—it’s only three vineyards. My first step is to take the three lots and make a proportional blend. Then I can play with the proportions and choose the best wine. I don’t ever do it in one sitting. I do it over several sittings—it’s that important.
[An aside: Cathy’s Cabernet Sauvignons are made of 100% Cabernet Sauvignon. Her blending process is blending wine that comes from different vineyards—not other grape varieties.]
M: Do you do it yourself or do you have your team taste with you?
C: Yes. The buck stops here. I believe that really good wine can be made by committee, but great wine cannot.
M: Can you give me a sense of how the terroir differs in each of your three vineyards?
C: They’re so close together, you can almost throw a rock between them. They’re all between Rutherford and Saint Helena. They’re all on the bench—that’s our jargon for alluvial fans. They’re extremely gravelly and well drained. They’re all loamy, so they all hold water well going into the early summer, but they run out of water because our summers are categorically rainless. That’s another very unusual thing in the world. They run out of water right when they ought to stop growing at veraison, right around the first of August. Mother Nature controls that.
The terroirs are so similar, that there’s way more tying them together than holding them apart. That said, though, each block is a little different. Sunbasket is even more gravelly than Kronos. We found parts in it that were 70% gravel. There are just slight differences in the soils. The vines have been planted at different times with different rootstocks, different trellising—all those things make really small but important differences that accumulate, so the wine speaks of that place.
M: Where do you see Napa Valley going in the next few years?
C: If we’re still farmers, we’ll be making great wine. I can’t make the wine any better than the grapes that come in the door. I spend most of my effort and time out in the vineyards. As an area gentrifies and becomes less rural and agricultural, I think that could be a threat to making great wine.
M: You’ve been a huge role model for women in the wine industry. How did you manage to build up your resiliency when you were first starting out?
C: It’s incredibly gratifying to me that I have mentored a lot of people over time. Resilience? It just comes from inside. It’s hard, you know? I’m still surprised at how little things have changed. I still need a lot of resilience myself. I guess it’s just passion—it’s a bunch of things. I grew up the eldest of four daughters. I studied biology at a small liberal arts school where there truly was no difference that I was a woman. Growing up I didn’t really know that I was a second class citizen until I got out of college. There’s a certain amount of confidence I built up, and just drive. I’ve always been grateful that the term winemaker connotes no gender. There’s absolutely nothing about winemaking that a woman can’t do. Period.
M: Do you have any advice for folks who are in a position to mentor more people?
C: Open up opportunities. I’ve always hired interns, even when I was making wine for other people throughout the 80s. Every year I hired an intern—that’s a wonderful opportunity to bring people in. It’s hard to find good people. If you cut out half of the population, you just cut out half of your potential pool—that’s just stupid.
M: Is there anything about winemaking recently where you’ve felt “wow this is my joy” moment?
C: Almost every day. But especially harvest. We only make wine once a year. Everything is leading up to that. We get one chance to make wine every year. No matter how old I live to be, I can count the amount of vintages left. Harvest is by far and away my favorite time. It’s very joyful for me.
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Non-profit pairing: Cathy supports many non-profits, but one of her favorites is the Napa Emergency Women’s Center, which is dedicated to providing safety, hope, healing and empowerment for survivors of domestic and sexual abuse. Donate to support this important non-profit here.
You can find Cathy Corison’s wines on her website. To support this inspiring winemaker, buy her wines directly from her website, or ask for them in your local wine shop. You can read more about Cathy Corison on SevenFifty and The New York Times.
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