Despite the fact that plants make up 80% of biomass on Earth, sociology rarely examines human- plant relationships. Human societies are inherently dependent on plants, most obviously as the basis of food supply, ecosystems, atmospheric and climate regulation, and water cycles, as well as for sources of oxygen, medicine, fuel, and fibre. Society, or terrestrial animal life for that matter, could not exist without plants. Based on this recognition, here we lay the foundations for sociological plant studies, a field that studies the dialectical relationship between human societies and plants. We ground this foundation in a realist-materialist perspective that recognises the ontological independence of plants and does not reduce them to human social constructions. We show how considering plants can help us to understand the emergence of civilisations, state formation, and mechanisation of production at the macro-level, and how human-plant interactions shape everyday life at a more micro-level. We present our formulation of sociological plant studies as a starting point for future research.