Monitor salts and pH, particularly for ivies. Remove saucers from ivy baskets to allow adequate drainage. All geranium types are intolerant of high soluble salts. The higher pH range for zonals and floribundas reduces the availability of excess Fe and Mn. Fe deficiency generally occurs on the youngest leaves first.
Upper leaves become chlorotic and show necrotic lesions on the undersides.
The leaves easily fall off with slight pressure. Probably the common practice of using water-soluble fertilizers containing trace elements has greatly reduced the occurrence of this problem. Begin fertilizing vigorous types shortly after transplanting. Excess soluble salts in seedling or early transplant stage. Marigolds, seed geranium, and common impatiens are most susceptible to this disorder characterized by bronze speckling to the leaves.