The Trellising Method That Boosts Efficiency and Brix

Titus Vineyards in St. Helena, California began its transition in the early 1990s from commercial grapegrower to winery. Shortly after, it redeveloped its vineyards, which were in need of replanting.

Today, the winery takes a “low-impact” approach to farming — which describes the effort to minimize the effects on the environment rather than the difficulty of the approach.

Co-owner and General Manager Eric Titus, whose pre-winery career was in environmental science, said one major change made during redevelopment was the installation of a vertical trellis system.

A vertical trellis system encourages a different expression and concentration of fruit than a sprawling trellis, which allows the vines to create a canopy over the fruit.

Titus said the method allows them to keep the canopy above the fruit itself and divide the plant into zones.

“What’s unique about it is you’re keeping the canopy above the fruit itself and dividing the plant more into zones,” Titus said. “The other way had the canopy shading the fruit, creating mottled sun exposure. With vertical, you get more sun exposure and you can orient the vineyard for equal morning sun and afternoon sun.”

The method can improve efficiency and make it easier to access the fruit during pruning, thinning and leafing operations early in the summer.

It’s also easier to check for ripeness and prevents damage from mildew.

Grapes for which the trellising method provides the most benefit include big, sun-hungry, full-bodied varietals like Cabernet Sauvignon and Merlot, Titus said.

“When the plants were shaded under a big canopy, the brix wasn’t as high at harvest and the vines have a really high brix potential,” Eric said. “Not that you want high brix, but you just pick it when you can.”

“During the mid 1990s, during all of the replanting that was going on, people including us were using the vertical shoot position system because the sun results in a more fruit-forward type of fruit with lower tannins, contributing to the styles of approachable wines that Napa Valley has trended toward.”