It has been used for over 2000 years, and was one of the first metals used by ancient civilizations. Immobile so youngest leaves first show sign of deficiency. Growing leaf tips start to die. Copper toxicity is a common occurrence, and often appears after copper sulfate has been used as a pesticide. Copper toxicity is rapid and complete plant death.
Copper is less available in alkaline soils, and in peat based soils and media.
Keep nutrient water pH at 7.0 or less to keep copper available to plants. Copper needs in plants Copper is an essential mineral for both plants and animals, but can be deadly in higher doses. It is used by the plant in the formation of chlorophyll, and is used to transport fluids. Copper deficiency in plants Copper deficiency first appears on the youngest leaves, showing up as yellowing, then dying leaf tips. In some plants, yellow patches appear on stems just below leaf nodes and later the patches can bulge out and fill with fluid.