b'Deficiency symptomsManganese deficiency symptoms are reduced growth and yield and the plant is more susceptible to pathogens.The symptoms are yellow spots between the veins in the leaf and then brown leaf edges. The symptoms resemble iron deficiency. Manganese deficiency is visible on both the youngest and older leaves, in contrast to iron deficiency, which only shows itself in the top of the plant.Lack of manganeseExcess symptomsExcess symptoms are common. Especially when the pH is too low, the veins in the older leaf turn brown, brown spots appear on the leaf and the leaf edges turn brown.ZincZinc is part of enzymes that, among other things, make the plant hormone auxin. This hormone controls plant growth and development; formation of new roots, leaves and flowers. It also ensures that roots grow down and the plant cells are strong.Therefore, the concentration of zinc in the stem tip is greatest and young leaves need more zinc than older leaves.120'