Dancing with the Vines

As our sole source of grapes, there’s no denying that our estate vineyards define our wines. With 440 acres of vines to nurture at an incredible level of detail, we have to be very thoughtful in our approach. With so much of the work done by hand, Jon says it’s more like gardening than farming and he takes direct inspiration from Katie “Nana” Trefethen, who was an avid gardener herself.

“In our vineyard office, we still have a framed quote from Katie Trefethen which reads: ‘Successful gardening is doing the right thing at the right time, whether you feel like it or not.’ I couldn’t agree with this more. Timing is everything. Our vineyard is a mosaic of different soil types, rootstocks, grape varieties, and clones and each part of the vineyard needs just the right attention at just the right time.” 

December to March is the most peaceful time in the vineyard, as the vines are dormant. After a busy and fruitful harvest season, they’ve earned the respite! The leaves have fallen off with the first frosty nights and only the trunks and canes of the vine remain. Beneath the soil, things are not so still. The roots are growing, soaking up soil nutrients to keep the vine strong while preparing for the emergence of new shoots in the spring. During this time, the vineyard team prepares the vines for the next growing season with winter pruning, one of the most crucial aspects of vineyard management.

“What we’re doing by pruning is removing and cutting back canes from last year’s growth and leaving just a few buds from which shoots will grow after budbreak. A wild grapevine’s nature is to use a tree as a natural trellis and continue growing upwards every year until it reaches the top of the tree canopy. So, we have to cut the vines back just to keep things at ground level.”

It’s actually a delicate and rather technical process. In fact, according to Jon, pruning and many of the other practices throughout the seasons are all about balancing the fruit and foliage-to get the right amount of energy from the leaves, which act as solar panels, while allowing dappled light to reach the grape clusters, for optimal flavor development. The act of pruning, which determines how many shoots will grow that season, has a direct impact on vine balance.

“If, for example, we leave 24 buds on a vine, we can expect around 24 shoots to emerge that spring. But vines have different levels of vigor, based on their age, their rootstock, and the soil type so they don’t all get the same number of buds. If we leave too many buds on a given vine, the shoots will be too short and there won’t be enough leaves to ripen the fruit. If we don’t leave enough buds, the same energy is channeled into fewer shoots and they will be too long, creating too much shade and requiring more work to cut them back. The vineyard team members are trained to evaluate each vine and adjust the number of buds accordingly so that we can set the stage, vine by vine, for appropriate balance and optimal ripening before harvest.”

The entire process requires constant adjusting, listening to the vineyard and learning, to gain the information we need to make informed decisions. It’s no wonder that learning is one of our core company values!

Springtime in temperate climates is associated with new growth—flowers are blooming, and leaves are growing back on the trees. The same can be said for the vineyards. The arrival of spring coincides with budbreak, the mark of a new growing season. In the Oak Knoll District of Napa Valley, our buds typically “break” in early March and the new shoots grow slowly until the temperatures warm up in April.

As the shoots really take off, we need to get into each vineyard block for suckering, which is simply the removal of all unwanted shoots. Maybe we got the number of shoots we wanted from pruning but now it looks too crowded or maybe the vine had so much energy that it is pushing out extra shoots, true suckers which lack fruit clusters. Proper suckering is another chance to fine-tune the vine balance and opening up the canopy improves air circulation which can help prevent mold and mildew. By late April or early May, flowering begins, and the vineyards are filled with the mesmerizing scent of white blossoms. 

Jon smiles and states, “It’s an amazing time of year. Chardonnay, Riesling, and Pinot Noir bloom earlier in the season and do everything a little ahead of the other varieties. As you can imagine, I’m grateful we have these different varieties on the estate because they’re ready for each of these viticultural practices at different times of the year. If we had to do the same practices across 440 acres of Chardonnay and Pinot, all ready at the same time, we’d be in trouble!”

During the flowering phase, known as bloom, each grape actually begins as a flower. These grapevines don’t need insects for pollination but winemakers cross their fingers for good weather during this period, as cold temperatures and rain can lead to poor fruit set, impacting the size of the crop.

 “As we get through bloom, we turn our attention to the next step in canopy management, the removal of individual leaves by hand. Sunshine is critical for flavor development and we are able to custom craft the light environment around each individual cluster.”

A complex process, canopy management refers to all the decisions and actions around pruning, suckering, and leaf removal. The overarching goal is to achieve the perfect balance of shade, sunlight, and air circulation around each cluster, promoting gorgeous fruit and optimal ripening. One key to success with canopy management is flexibility, even with one’s schedule. 

“It’s a block-by-block, vine-by-vine, shoot-by-shoot process. Some weeks we need to work more hours than others, often including Saturdays. The vine doesn’t know it’s a weekend, and if it needs our attention, we have to be there. That’s why it’s so amazing to have a dedicated in-house crew. The truth is nature is messy. And so no matter how good we are at pruning, no matter how good we are at vineyard design, Mother Nature always takes the lead.”

Immediately following the fruit set, the grape berries are still small and green. At this stage, the grapes have very little sugar but are very high in acid. Veraison brings about a color change in the vineyard—with the berries beginning to soften and turn into various shades of purple or golden-green, depending on their variety. During this time, the Trefethen vineyard team begins to adjust the crop rather than the canopy. This “cluster thinning,” the removal of specific grape clusters, helps achieve yield and quality goals.

“It’s an intense process as we are dropping perfectly good fruit on the ground. But we are farming for quality here, not quantity, and sometimes it’s just what is needed for a final touch to get that perfect level of vine balance.” 

As the grapes continue to ripen, sugars increase and acids decrease while tannins and other phenolics develop. Harvest typically begins in late August or early September for Trefethen, and all the grapes are picked by hand. The decision to pick an individual block or just a couple of rows on a given day comes from our winemaker, Bryan Kays. He spends his mornings during harvest walking the vineyard, evaluating the grapes, and making plans for the next day’s picking. At Trefethen, the harvest can last as long as two and a half months. It’s a full season out of the year because we have these nine different varieties. We typically start with our Riesling, Sauvignon Blanc, Chardonnay, Pinot Noir, and Cabernet Franc. Then we move onto our Merlot, Malbec, and eventually our Cabernet Sauvignon and Petit Verdot. It’s a long stretch!

Jon adds, “It is a lot of work and the pride among our team is tangible. You can hear the laughter, the singing, and the excitement as you approach the vineyard. It is truly a thrilling time of year.”

As this journal entry is being finalized in April 2021, the vines are already off and running with the new vintage. It’s almost as if the buds awaken from their deep winter hibernation to the smell of coffee and sizzling bacon. The roots start to pump water and stored nutrients through the groggy vine, starting quietly, and gradually becoming more forceful as the season progresses. The vineyard team is working diligently to keep up with the growing vines.

“After a few years of working at Trefethen, I asked Alfonso Beas, our longtime Ranch Foreman, what was different about our vineyard practices since I’d arrived. He answered in Spanish, ‘más movimiento’, meaning more movement. He was reflecting on how we had broken the vineyard down into smaller and smaller pieces and worked diligently to get to each block for each task at just the right time. It’s a dance with nature. And it’s not one that you can watch from the sidelines. You’ve got to get off your chair and get onto that dance floor! But remember: we’re not even the ones leading. We take our cues from Mother Nature and move hand in hand.”