In this paper we discuss research work that enables the development of mixed societies of communicating plants and artefacts. PLANTS is an EU-funded Research and Development project, which aims to investigate methods of creating “interfaces” between artefacts and plants in order to enable people to form mixed, interacting (potentially co-operating) communities. Amongst others the project aims to develop hardware and software components that should enable a seamless interaction between plants and artefacts in scenarios ranging from domestic plant care to precision agriculture. This paper deals with the approach that we follow for the development of the homonymous system and discusses its architecture with special focus on describing the communication among artefacts and plants and on designing an ontology that provides a formal definition of the domain under consideration.