Bonterra Tests Robots to Fight Vineyard Disease

Bonterra Organic Estates said on Monday that it has begun a pilot program with Saga Robotics to use autonomous electric robots in its estate vineyards in inland Mendocino County, Calif., in a move the company says could reduce fungicide use, cut carbon emissions and lessen the impact of farming on soil.

The project will place six Thorvald robots across about 200 acres of Bonterra’s vineyards in Hopland, where the machines will move through rows at night and apply ultraviolet-C light to vine canopies. The light is intended to disrupt fungal DNA and prevent diseases such as powdery mildew, botrytis and sour rot from spreading. Bonterra said the system is designed as an alternative to sulfur-based spray programs commonly used in organic vineyards.

The company said the robots weigh about 900 pounds, or roughly one-tenth the weight of a conventional tractor and spray rig, which it said should reduce soil compaction and other disruption in the vineyard. The robots are fully electric and powered by renewable energy sourced by Bonterra.

Joseph Brinkley, Bonterra’s senior director of regenerative organic development, said the company was trying to find ways to lower its environmental footprint while making its farming systems more resilient. Caine Thompson, general manager of Saga Robotics U.S., said the partnership showed how technology could change how wine grapes are grown.

Bonterra said research trials, including a peer-reviewed study from Cornell University, have found that ultraviolet-C treatments can match or outperform traditional fungicide programs in controlling disease without harming vine growth, yield or fruit quality. The company said the pilot is part of a broader effort to combine organic farming with new tools that can improve vineyard management while preserving ecosystem health.

Founded in Mendocino County in 1968 as Fetzer Vineyards, Bonterra is now part of Viña Concha y Toro and markets itself as a leader in organic and regenerative winegrowing. The company said the pilot reflects its push to keep refining vineyard practices as growers face pressure to reduce inputs and adapt to changing conditions in California wine country.