Potassium is needed to plants in order to better absorb carbon dioxide from the air, in addition, it increases the resistance of plants to frost, drought, pests and diseases. Solutions of potash fertilizers can be introduced into any soil, they are brought deep into the earth. Sulfuric acid and potassium chloride are used, as well as so-called “potassium salt”.
Potassium chloride contains 50-60% potassium and the other – harmful in large doses for plants is chlorine. If the plant is sensitive to chlorine (berry crops, especially strawberries), feeding make in advance so that the chlorine goes to the bottom layer of the soil. Potassium chloride is used in autumn, when digging at the rate of 20-25 g/sq. m.
Sulfuric sour potassium (46%) is the best choice of fertilizer for berries and fruit crops. It does not contain harmful impurities of chlorine, sodium or magnesium. It is applied in autumn or spring mixed with another fertilizer at a consumption 20-25 g/m2, and for feeding it is enough 5-10 grams.
“Potassium salt” is a combination of potassium chloride with sylvinite and contains 30-40% of the active substance. At the basic entering it is necessary 10-20 g / sq.m.