The floral analyses of iron content allowed the prognosis of the incidence of the iron chlorosis on peach traes (Prunus persica L. Batsch), c.v. 'Babygold 7' grafted on seedling, with high reliability. From a total of 35 peach traes analysed, six of them with floral iron concentration in dry matter less than 133 ppm were selected. These six trees further developed a severa iron chlorosis in leaves. The early correction of this deficiency permitted to measure its influence on the fruit quality, doubling the sizes and avoiding the delay into fruit ripeness for the corrected trees.