Arable weeds have drastically declined over the last decades, yet, even if they can have detrimental effects on crop production, weeds are of key value for the maintenance of biodiversity and the delivery of pollination and pest control services in agroecosystems. Agroecological weed management should thus aims at maintaining weed diversity, preventing weed outbreaks while reducing herbicide use. Local management practices and properties of the wider landscape can contribute in combination, rather than separately, to achieving this aim. They can directly shape the composition of weed communities, and, indirectly, promote organisms that regulate weeds. In this talk, I present a framework to assess the multifunctionality of weed communities in real landscapes and show how the compositional and configurational heterogeneity of crop mosaics can create interesting trade-offs between weed services and disservices at a landscape level. I also present results illustrating how the interplay between field-scale management and landscape properties can affect weed seed predators and ultimately the biological regulation of weeds. Both examples highlight the benefits of diversifying landscapes and farming management for biodiversity and the delivery of ecosystem services.