Things are not just consumable, they are made so. They acquire their ‘materiality' not only through engagements with them as finished products, but also through processes that make them material, i.e. technical activities. This field of study in anthropology, rejected by dominant trends because of its deterministic connotations, is a useful way to explore processes of materialisation and to investigate the ‘inbuilt' relationality of things and activities. This paper focuses on yam gardening in Nyamikum, an Abelam village of the East Sepik. Once harvested, long (and short) yams emerge not solely as phallic symbols, but also as artefacts, representations, living beings, ancestors, artworks, valuables and, mostly, food. Starting observations at the beginning of the operational sequences (‘chaıˆnes ope´ratoire', Lemonnier 1992) within gardening techniques, a combination of gestures, body, materials, energy, tools, knowledge and behaviours takes us across domains of experience (embodiments, transformations, sociality, narratives) to illuminate how yams are made into ‘relational' entities. They demonstrate that techniques create a web that materialises social and cultural values, condensing networks of relations into things. As the results of these (known or imagined) processes, things can demonstrate the material validities of representational—or ideological— components of technological phenomena and may be used to generate sociality.