Potassium (generally referred to as ‘potash’) is a major nutrient which is required by all crops. It is second only to nitrogen in the amounts required by the crop. It is highly mobile and is quickly distributed within the plant.
The main role of potassium in the plant is as a water regulator and in this role it influences many plant processes. It is particularly important in the regulation of cell water content, cell turgidity and rates of transpiration. The translocation of photosynthesates and a number of plant enzymes all depend on potassium.
Low levels of potassium will seriously affect crop growth, quality and yield.
Potassium deficiency affects a wide range of arable and horticultural crops. The visual symptoms of potassium deficiency are usually seen in crops on light sandy soils or chalk soils.
More common however is a reduction in plant size due to reduced potassium uptake. The visual symptoms of extreme deficiency are seen first on the older leaves. Most crops exhibit a yellowing of leaf margins which extends to the midrib as the deficiency becomes more severe. This eventually results in leaf necrosis, particularly at the margins.
Use K50 when potash deficiency is diagnosed or suspected, or as part of a nutrient management programme on potatoes. Foliar uptake will be enhanced by the addition of SW7¹.
Apply 2-5 l/ha, in a minimum of 200 l/ha water.
The spray tank should be filled with half the required water. If applicable, add the required amount of SW7 to the water before the K50. After shaking the container, measure the required amount of K50 and add to the tank whilst maintaining constant agitation. Add remaining water to correct dilution and spray.
Do not apply in tank mix with pesticides when crop is showing deficiency symptoms, is under stress, or in adverse weather conditions.
For further information on compatibility and tank mixing, and for physical compatibility with pesticides refer to the compatibility guide PDF.
¹ SW7 is an adjuvant designed to help with improved wetting and spreading of the spray solution on the leaf surface. SW7 should be added at 0.1% of the spray volume, e.g. 100 ml in 100 litres of water. Maintain agitation and apply immediately after mixing.
K50 is ideal source of potassium (potash), which is vital nutrient for all plants. Potassium deficiency can be visual in leaves and can result in necrosis.
Use K50 when potash deficiency is diagnosed or suspected, or as part of a nutrient management programme.
For further information about timing and application rates, please refer to the K50 Technical Information for Horticulture