Agresol Limited

Potassium is more soluble than phosphate and requires regular addition to achieve consistent, good crop yields. The element is associated with stem strength, flower production and even ripening. Potassium is also associated with both water retention in the plant and the metabolism of certain trace elements. Though Potassium is involved in a number of plant enzyme systems, its role is to regulate processes within the plant rather than to be fixed in one form.

The behaviour of Potassium in the soil is greatly influenced by soil type. Lighter soils generally are less able to retain supplies of Potassium, and thus there is a more critical requirement for regular additions. High clay content soils will hold greater exchangeable reserves than sandy soils and consequently are able to supply crop requirements with limited additions of fertiliser.

Deficiency symptoms occur most readily on lighter soils, and are most commonly seen on older leaves. Some stunting of growth may occur, and there is a loss of turgor, making crops less drought resistant. Increases in organic matter and the use of high organic manures can help to limit deficiencies in lighter soils.

High application rates to grazing grassland should be carefully timed to avoid excessive Potash application that could significantly interact with Magnesium metabolism. High application rates to grazing land should only be considered in the autumn and early winter. Application to conservation (hay or silage) land may continue into spring without excessive risk. Applications to arable crops may proceed at any time, but it should be noted that there may be some inhibition to Magnesium activity, and sites with low Mg indices should be assessed carefully, and deficiency symptoms noted.

Sewage type materials are generally low in Potash. Dairy products tend to be higher.

Analytical results usually refer to Potassium. To convert this to POTASH (K2O), multiply the result by 1.205. To convert kgs / Ha to units per acre, multiply the kgs/Ha number by 80%.