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Folanx® CarboK - the NK fertilizer solution

Nutrients and their functions: Potassium (K)

Potassium is chemically bonded to the clay-humus complex and is therefore relatively unavailable in light soils. During periods of drought, on the other hand, soils with high clay contents can promote potassium deficiency. Experts call this phenomenon potassium fixing, on account of the fixed bond to the clay particles in the soil.

Potassium deficiency is expressed in a disruption of the water economy of the plants, because potassium controls the water economy and therefore also the transport of nutrients. If the water economy is disrupted by a drought or if the plants have high water requirements, a potassium deficiency leads to premature withering phenomena. The result is an increased susceptibility to disease, pathogens and pests and deficient formation of buds and roots. The delayed ripening of the fruit reduces its quality.

The use of liquid potassium fertilizers has the advantage over soil fertilizers that the chloride and/or sulfate load on the soil is reduced, which therefore reduces chloride damage, principally in grapevines.

Potassium applications supplement calcium and magnesium fertilization to create an equilibrium between potassium and calcium in the foliage and potassium, calcium and magnesium in the fruit. In fruit farming, potassium promotes the coloration of the fruit and reduces drought stress with a good crop in the summer.
General symptoms of potassium deficiency
Typical symptoms of a potassium deficiency are leaf edges that are first yellowish and then turn brown. These symptoms generally appear on the older leaves. The fruit remains small and the content is reduced. Grape growth is also disrupted.
In cases of very severe deficiency, the leaves in the area of the grapes can become dry and withered in July or August, which can result in a total loss of the crop. Unripe wood is also the result of increased sensitivity to winter frost. This deficiency is triggered as early as in the spring, especially in clay-poor soils and on clayey soils under drought conditions.
Fruit farming
A typical symptom of potassium deficiency is brown, necrotic leaf edges. In the early stage, these edges are still light green to yellow. The average fruit size is smaller and the fruit is more susceptible to diseases. The storage properties of the fruit are also adversely affected. For example, apples under-supplied with potassium are significantly more sensitive to damage from cold.
Berry farming
Highly humus and sandy soils generally contain too little potassium. A potassium deficiency in berry farming can be recognized by grown leaf edges and brown spots. These symptoms can also occur on the leaf stems.

The plants, especially strawberries, have a wilted appearance. Side roots and runners are reduced. The taste of the fruit is somewhat insipid and shelf life is significantly reduced. Bud set for the following year will be reduced.