Abstract Recently, urban agriculture has spread rapidly in occidental cities taking the form of plant cultivation on the rooftops of urban buildings. In this context, it would be interesting to use a natural fertilizer present in cities like the pigeon ( Columba livia ) guano. In this study, we tested the effects of pigeon guano on the cherry tomato plant in an urban environment. On a rooftop at Ivry‐sur‐Seine (near Paris, France), we set up 30 cultivation bags (58.9 L volume) with two cherry tomato plants in each bag. In June 2017, we added about 15 g of pigeon guano in 1.5 L of water to each of the 15 “guano” bags and 1.5 L of water to each of the 15 “control” bags. After 15 days, we observed that the tomato plants were higher and tend to have more flowers in the guano treatment than in the control group. Finally, regarding the total number of cherry tomatoes harvested (total mass and number), it was around one to two times higher in the guano treatment than in the control. However, the average mass per fruit was not affected by the treatment. Overall, we showed that pigeon guano is an efficient local fertilizer for cherry tomato plants in urban areas.