Potassium is used by plants in relatively large amounts. It is vital for regulating water uptake and loss, CO2 uptake through the breathing pores called stomata which are found on the underside of leaves, helps improve drought resistance and activates certain enzymes. Potassium has a big impact on most aspects of the quality of harvested produce. Potassium is an essential element for healthy plant growth and development. It is found in a wide range of soils and the plants need it to build strong cell walls, transport nutrients around their bodies, activate enzymes, facilitate photosynthesis and carry on many other functions.
Plants need potassium in order to produce carbohydrates and protein. Potassium also helps stimulate the plant's growth and defensive systems, which helps prevent diseases and insect damages.
Too little Potassium can cause the leaves to yellow between the veins and leaf tip burn. Too much Potassium causes a metallic, soapy taste to develop in the smoke and nutrient burn can occur on the leaves.
Mild deficiencies can result in marginal leaf yellowing, but the veins remain green. As the deficiency progresses, the leaf tips die and turn brown followed by leaf edges. Burned areas appear on the newest growth and yellowing of entire leaves occurs between the veins. Stems and branches may be weak, brown and brittle.