Low‐Power Electric Mulch Provides Effective Intra‐Row Vineyard Weed Control, but Only at Small Scales

ABSTRACT Electrical weed control is becoming a viable option for weed management in many cropping systems including vineyards. Commercially available devices treat emerged weeds with high‐power electricity, controlling weeds with efficacy similar to herbicides. However, purchase and operating costs of these mobile tractor‐mounted devices are high, limiting their adoption, especially among small‐scale producers. We have developed a low‐power electric weed control device (‘electric mulch’) that can effectively and safely prevent weed growth over small areas. Electric mulch uses a 5‐watt solar panel with a voltage booster to deliver up to 300 V to a metal screen placed on the ground. As weeds emerge, they contact the screen, completing an electrical circuit such that electricity flows through the weeds and prevents growth. While electric mulch has been demonstrated in small xeriscaping scenarios, this is its first test in an agricultural setting. In 2023, we established 1.5 m × 1.4 m plots in two New Mexico vineyards. We compared electric mulch to pendimethalin (6.6 kg ai ha −1 ), plastic mulch and an unweeded control for intra‐row weed control. In 2024, we tested different treated area sizes of electric mulch, including 0.4, 1.9, 3.7, 5.6 and 6.5 m 2 in one vineyard. In 2023, electric mulch provided season‐long weed control equal to plastic mulch and better than herbicide, with weed cover less than ~5%. In the 2024 experiment to test treated area sizes, weed cover remained below 5% in all areas through mid‐July. However, as the summer progressed, electric mulch efficacy declined non‐linearly with treated area size, and cover reached 35% in the largest treated areas by grape harvest. The decline in weed control efficacy with area is attributed to the inability of electric mulch to kill weeds after wet periods. While effective at small scales, additional research is needed to safely and effectively increase system power to facilitate larger‐scale operation.