Abstract: The invention relates to a computer-implemented method comprising:—acquiring (406) first training images (108) using a first image acquisition technique (104), each first training image depicting a plant-related motive; —acquiring (402) second training images (106) using a second image acquisition technique (102), each second training image depicting the motive depicted in a respective one of the first training images; —automatically assigning (404) at least one label (150, 152, 154) to each of the acquired second training images; —spatially aligning (408) the first and second training images which are depicting the same one of the motives into an aligned training image pair; —training (410) a machine-learning model (132) as a function of the aligned training image pairs and the labels, wherein during the training the machine-learning model (132) learns to automatically assign one or more labels (250, 252, 254) to any test image (205) acquired with the first image acquisition technique which depicts a plant-r