Productive function of urban gardening: estimate of the yield and nutritional value of social gardens in Prato (Italy)

The impact of urban gardens on food production and nutrient supply is widely recognized in the literature but seldom quantified. In this paper, we present the results of a semi-structured interview conducted in the ‘social gardens’ of Prato (Italy), i.e. areas of land assigned by the Municipality to individual pensioners or unemployed people for the cultivation of vegetables intended for domestic consumption. Some demographic and socio-economic aspects, the cultivated crops and the related areas were investigated. Starting from the areas, the total production of vegetables and their minerals and vitamins contents were estimated. The typical gardener was male, retired, with an average age of 74, and a low level of education. Gardening enabled pensioners to utilize their free time, facilitated physical activity, promoted socialization, and stimulated self-esteem. A 50 m2 plot cultivated on 40% of the area produced an estimated amount of 90 kg of vegetables per year, equivalent to approximately 61.5% of a person's fruit and vegetable needs. Tomato, by far the predominant species, occupied more than 80% of the cultivated area. The highest contributions to nutrients intake concerned Vitamin C and Vitamin A, the lowest Ca and Na. A higher yield and a greater and more balanced nutrient supply could be easily obtained through better use of the land (reduction of uncultivated area and greater assortment of vegetables). In our view, raising gardeners' awareness of this aspect and involving them in training programs on agricultural practices, vegetables composition, and nutrition, could be helpful for increasing the nutrient productivity of the plots and, ultimately, for strengthening the productive function of social gardens.