  Fruit size and leaf area are important indicators for plant health and are of
interest for plant nutrient management, plant protection and harvest. In this
research, an image-based method for measuring the fruit volume as well as the
leaf area for cabbage is presented. For this purpose, a mask region-based
convolutional neural network (Mask R-CNN) was trained to segment the cabbage
fruit from the leaves and assign it to the corresponding plant. The results
indicated that even with a single camera, the developed method can provide a
calculation accuracy of fruit size of 92.6% and an accuracy of leaf area of
89.8% on individual plant level.
