Chelates in agriculture

Within the past 20–25 years it has been recognized that many of the micronutrient requirements of plants could be supplied by complexes containing chelated metals. These chelates find uses in a wide variety of agricultural crops such as: corn, bush beans, cucumbers and citrus groves. Applications vary from fertilizer additives and seed dressing to foliar sprays and hydroponics. The chelates themselves have chemical structures that seem to be limited only by the chemists imagination. The critical factors for the use of any of these chelates is the stability constant and the cost to prepare a pound of chelated metal such as iron or zinc. A comparison of costs for a few of the more common chelates indicates a need for agricultural studies on the results of using glucoheptonates for supplying micronutrients.