‘A hundred plants, a hundred names’. Ethnographic field surveys have given us a collection of plant names and uses in Lower Brittany, which reveal the motivational types behind the various plant names. These include colours, numbers, sensory properties, mechanical properties, therapeutic properties, morphological and anatomical features, analogies with other plants or animal organs, and religious connotations. A lexical analysis reveals how society conceives companion planting. The art of attributing names, which are coded by cultural, social and technical frameworks, emerges from these fundamental categories.