In southern Europe, traditionally managed chestnut orchards are iconic landscapes and habitats rich in biodiversity. They consist of a spaced stand of grafted chestnut trees for fruit production and a herbaceous understorey layer. Management practises play a key role in maintaining and shaping the understorey vegetation layer, which supports most of the vegetation diversity. However, very little is known about thoughts, feelings, and attitudes of growers to the plant species which make up the understorey ground vegetation. To probe further on this issue, we performed qualitative socio-ecological research involving 38 growers to explore their perceptions and attitudes towards the understorey vegetation of selected chestnut orchards of the northern Apennines. Although most of the respondents were in their 60 s, they showed a wide range of cultural backgrounds and shared the common passion for chestnut cultivation. Biodiversity proved to be a difficult concept for the interviewees to understand and deal with. Nevertheless, the interviews based on both closed and open-ended questions made it possible to record 140 plant taxa. Among them, species with conspicuous flowers (e.g., orchids), species requiring management effort, and species providing practical benefits according to local tradition. Understanding and knowing the ecosystem complexity of the chestnut orchards could guide growers towards more adequate and biodiversity-enhancing management practises. There is, however, an urgent need to increase biodiversity awareness among chestnut growers (e.g., through training courses) to enhance and ensure the conservation of the traditional chestnut orchards and related biodiversity.