The objective of this study is to develop a non-destructive growth measurement of the plug seedlings population by the model that describes the relationship between the growth of plug seedlings populations and growth indices obtained from their image information. In this paper, the non-destructive measurement of the top fresh weight of the cabbage plug seedlings population based on three types of soil coverage models was examined. To calculate the soil coverage, binary images of cabbage plug seedlings were extracted using the chromaticity level of g component. The predicted top fresh weights of test plug seedlings populations based on the soil coverage model were fitted well with the actual them, and the best coefficient of determination R² was 0.90.