Weed control in vineyards often relies on intensive tillage, which can negatively affect soil health. While cover crops offer potential benefits (such as weed suppression and soil improvement), they may also compete with grapevines. Few studies have examined inter-row management from a functional perspective. Understanding how soil management shapes inter-row plant communities is essential to support beneficial groundcover–vine interactions and foster plant assemblages that deliver multiple ecosystem services. To fill this gap, we assessed how different inter-row soil management strategies influence plant biomass, diversity, and functional traits (specific leaf area, height, and Grime strategies) in two farms in Chianti Classico (Italy). Treatments included tillage, mulched spontaneous vegetation, green-manured pigeon bean (Vicia faba var. minor), and a barley–clover (Hordeum vulgare–Trifolium squarrosum) mixture, either mulched or green-manured. This is the first research on the topic based on data of biomass by species. Soil management significantly influenced inter-row biomass, species diversity, and plant traits. Tillage reduced biomass and selected homogenous, high-specific leaf area communities. In spring, cover crops yielded more biomass than tillage; pigeon bean was most productive and led to less diverse plant communities. Mulched cover crops supported less competitive assemblages in autumn, though autumn sowing may increase erosion risks. Mulched spontaneous vegetation maintained permanent soil cover but selected stable, competitive plant assemblages. Overall, mulched groundcovers can enhance biodiversity without compromising grapevine yield. Alternating sown and spontaneous mulched vegetation presents a promising, sustainable alternative to tillage, promoting soil conservation and supporting functionally diverse plant communities in vineyard inter-rows.
