Potassium fertilizers – the importance of potassium in plant cultivation?

Potassium together with calcium plays a key role in the process of plant water intake. K+ and Ca2+ cations regulate plant water management by controlling the transpiration process. The potassium ions cause the opening and Ca2+ the closing of the leaf stomas. According to recent studies, more than 60 different enzyme reactions are activated by the potassium ion. Potassium increases the plants’ resistance to frost and diseases. It was also shown to have a beneficial effect on the postharvest life duration of plants. In the case of potatoes, a good supply of potassium improves the accumulation of starch in the tubers and reduces their susceptibility to darkening of the flesh before and after cooking. As a result, tubers of potato varieties intended for fries and chips get a better colour after frying. The development of plants should be carefully monitored and intervened as soon as the first symptoms of deficiency of this element appear. In order to supplement potassium deficiencies, we recommend to use of mineral potassium fertilizers.


  • About 40% of soils in Poland are low and very low in potassium!
  • The effect of the yield seasonality comes from an unbalanced potassium demand!
  • Rapeseed and sugar beet take about 250- 400 kg·ha-1 of potassium per year!
  • The symptoms of potassium deficiency are chlorosis (yellowish discoloration of older leaves, first found on the tops of the leaf blade), necrotic spots (yellowish-brown leaf spots) and leaf curl!