Cover Crops Trap Copper Fungicides in Vineyards

A new study suggests that cover crops in vineyards can do more than protect the soil from erosion and help manage weeds. They may also intercept copper-based fungicides before those chemicals reach the ground, offering growers a practical way to reduce contamination in vineyard soils.

The research, published in the Journal of Environmental Management, examined whether different cover crop species could capture copper residues from Bordeaux mixture and other copper fungicides commonly sprayed in viticulture to control fungal diseases. Copper remains one of the most widely used tools in grape growing, especially where disease pressure is high, but repeated applications can cause copper to build up in the soil over time. That accumulation has raised concerns among scientists, regulators and growers because excess copper can affect soil health and nearby ecosystems.

In the study, researchers tested several cover crops for their ability to trap copper compounds after spraying. They found that some species were effective at intercepting the fungicide before it reached the soil beneath the vine rows. The result was a measurable reduction in copper accumulation in the ground below the vines.

The findings point to a simple change in vineyard management that could help address a long-running environmental problem without forcing growers to abandon copper fungicides altogether. For many wine regions, that matters because copper-based sprays remain important for disease control, particularly in wet seasons when fungal pressure rises.

The study adds to a growing body of work on how vineyards can use living ground cover as part of a broader sustainability strategy. Cover crops are already used in many vineyards to improve water management, support biodiversity and reduce runoff. This research suggests they may also serve as a buffer against chemical contamination.

The authors said the approach could help preserve soil health while allowing growers to continue using copper where it is still needed for crop protection. That balance is increasingly important as wine producers face pressure to cut environmental impacts while maintaining yields and fruit quality.