Figure 6.

Differences in crop yields per growing cycle between hydroponic systems and soil‐based systems in urban environments for six disaggregated categories of crops. Boxplots represent the first quartile (bottom end of the box), the median (band inside the box) and the third quartile (top end of the box). Error bars represent the minimum and maximum values of crop yields within the 1.5 interquartile range of the lower and upper quartiles, respectively. Red diamonds show the mean. ** = p < 0.01; *** = p < 0.001 (independent two‐sample t‐test).