| abstract |
The present invention is directed to micronutrients and compositions, and to methods for their preparation and administration to plants. The micronutrient compositions include chelated metal ions of the transition and alkaline earth metals The chelated metal solutions are prepared by complexing metal cations using an organic phosphonic acid The micronutrient compositions are stable at the pH about 6.5-9. The source of the metal ions may be any biologically acceptable metal salt, such as chloride, sulfate, nitrate, oxide, hydroxide and carbonate and other biologically compatible salts of the metal cations. The preferred chelating agents are aminophosphonic acids, such as ethylenediaminetetramethylene phosphonic acid. Micronutrient solutions containing such chelated metals are stable at neutral and alkaline pH and are used as liquid fertilizers, or mixed with other fertilizers to prepare clear, liquid fertilizer compositions for delivery of trace metals to plants. |