Comparison of control and treatment in a model site of optimal nutrition of citrus orchards. In this model site, a few meters away from orange trees under the nutrition management of Sabzafarin Arta Javid Company, and the opposite side has been maintained according to the gardener’s custom. The greenness of the trees, coping with heat stress, the size of the leaf blade and the difference in fruit size are among the highlights of the design. Thanks to Mr. Engineer Zeighami, the esteemed gardener, and Ms. Yousefzadeh, the esteemed expert of the company’s head office