Student interest in plants is lacking. Therefore, we investigated potential drivers of situational interest in cultivated plants and interactions between different dimensions of interest, i.e. topic, context and learning activity. A total of 462 high school students (14-17 years of age) rated two sets of questionnaire items combining eight plants (representing topics) either with different contexts or with different activities. We used Rasch analyses and multivariate analyses of variance to investigate which dimension of interest drove the students' interest. Contexts were the dominant dimension of plant-context combinations. Students were most interested in plants in reference to the contexts 'risks and the assessment of risks' and 'impacts on the environment'. Plants were the dominant dimension of plant-activity combinations. Students were most interested in activities in reference to cannabis (psychoactive plant), cocoa (stimulant plant) and arnica (medicinal plant). For these three plants, the least interesting activity ('working with scientific texts') was more interesting than the most interesting activity ('completing a computer simulation') for the other five plants. Plants, thus, moderated the general level of interest students expressed in plant-activity combinations. We discuss the findings in terms of the choices educators can make for contextualizing plants and for selecting plants for classroom activities.