Recent sustainable HCI research has advocated "working with nature" as a potentially efficacious alternative to human efforts to control it: yet it is less clear how to do so. We contribute to the theoretical aspect of this research by presenting an ethnographic study on alternative farming practices, in which the farm is not so much a system but an assemblage characterized by multiple systems or rationalities always evolving and changing. In them, relationships among species alternate between mutually beneficial in one moment (or season), and harmful in the next. If HCI is to participate in and to support working with nature, we believe that it will have to situate itself within such assemblages and temporalities. In this work, we look into nontraditional users (e.g., nonhumans) and emerging forms of uses (e.g., interactions between human and other species) to help open a design space for technological interventions. We offer three ethnographic accounts in which farmers-and ourselves as researchers-learn to notice, respond, and engage in symbiotic encounters with companion species and the living soil itself. CCS CONCEPTS • Social and professional topics → Sustainability; • Human-centered computing → Empirical studies in interaction design.