Selection of plant species for permanent ground cover in vineyards: Looking for an agronomic and environmental optimum

Abstract

The installation of a permanent ground cover in vineyards offers numerous agronomic (soil protection, soil fertility) and environmental (reduced leaching of nutrients and of plant protection products, reduced use of herbicides, biodiversity) benefits. Nevertheless, such ground covers are not always free of drawbacks (competition for water and nitrogen, increased risk of frost, management). For the growers, the challenge is to manage the green ground covers in such a way as to preserve their advantages while limiting these drawbacks. Among the tools available to the winegrower is the sowing of a seed mixture composed of selected species: a choice depending of the soil and climatic conditions of the parcel, but also of the different, and sometime contradictory, objectives of the grower. This paper lists the agronomic and environmental issues addressed by the installation of a permanent ground cover in vineyards. It describes two concrete situations – ground cover for vineyards integrated in agro-ecological networks and green cover on the row of vines (as alternative to glyphosate) – for which, according to the objectives and the impacts, a choice of plant species is proposed. At last, it presents the trials now carried out to validate and optimize those selections, as well as the first observations and results gathered to date.