Industrial agriculture has led to many environmental and economic issues. As a result local production such as urban farming is a promising alternative, but the feaseability of urban farming has not been studied in details so far. Agronomists Sanyé-Mengual et al. grew lettuce, tomato, chilli pepper, eggplant, melon and watermelon on rooftop gardens in Bologna, Italy. They found that floating cultivation of lettuce in the summer is better to address global warming. Soil cultivation of eggplant was the cheapest at 0.13 Euro per kg.