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Weeds can cooperate with the agroecosystem&#8217;s functioning by providing ecosystem services. Effective weed management should mitigate negative weed&#8722;crop interference, while maintaining a functional and balanced weed community. In a two-year trial, the in-line/roller crimper (RC) was used to terminate an agroecological service crop (ASC; here barley, <i>Hordeum vulgare</i> L.) before organic zucchini (<i>Cucurbita pepo</i>, L.) and compared with green manure (GM) ASC and tilled no-ASC with Mater-Bi mulch on the rows (No_ASC). Zucchini yield, soil N availability, weed density/cover, biomass, and community composition were assessed. Analysis of variance, exploratory statistical analysis, and non-parametric inferential approaches were run, respectively, on agronomic data, species-specific weed frequencies, and Shannon diversity. Zucchini yield was the highest in No_ASC, due to soil N immobilization under high C:N barley residues in GM and RC. Multivariate analysis discriminated RC from tilled systems, outlining a specific <i>ensemble</i> of weed species correlated to Shannon diversity. From zucchini fruit set, RC selectively favored <i>Polygonum aviculare</i> L. and <i>Helminthotheca echioides</i> (L.), reasonably because of their oligotrophy and creeping habit. Their dominance finally caused low RC weed control. Results highlight strong weed selective pressure by the mulch-based no-tillage. Understanding the mechanisms underpinning the impact of soil management practices on weed community can drive towards a tailor-made and more effective weed management.