Green roofs (GRs) are typically used to retain stormwater and are increasingly being used to produce food by growing edible vegetation, such as Mad Hatter Peppers (Capsicum baccatum). However, there have been conflicting studies on whether GRs can feasibly produce Capsicum baccatum in GRs compared to inground production. To test this, water retention was compared among small-scale models of three different vegetation types: two Sedum setups, two Capsicum baccatum setups, and one bare setup. The models used water storage compartments and moisture retention fabric to increase water retention and to reduce the need for irrigation. There was not a statistically significant difference in water retention between the different vegetation types, and the Capsicum baccatum wilted by the end of the study, so it did not produce food. These results indicate that Sedum should be used in future GRs because they can provide many benefits other than water retention, whereas Capsicum baccatum may not be healthy enough to provide other benefits.

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