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Potassium Deficiency


Potassium Deficiency

Usually appear in

Spring to Autumn.

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Caused By:-     Various causes


Potassium is important to plant growth and development it provides the appropriate ionic environment for metabolic processes and growth regulation. Potassium helps plants grow faster, Use water better and be more drought resistant, Fight off disease, Resist pests, Grow stronger and Produce more crops. Typical symptoms of potassium deficiency in plants include brown scorching and curling of leaf tips as well as chlorosis(yellowing) between leaf veins. The leaves of the plant appear dull and are often blue-green in colour with inter-veinal chlorosis. Brown spots may also appear on the leaf. Plant growth may be stunted, root development may be poor, and flowering, seed and fruit production will be diminished or non existent. It is more often found on light, sandy soils, as well as chalky or peaty soils with a low clay content. It is also found on heavy clays with a poor structure. Soils with hif=gh Organic materials rarely suffers from this deficiency. Older leaves are usually the first to suffer as potassium can be moved to support new growth. Plants may not be as hardy and disease resistant if they lack potassium. The deficiency most commonly affects fruits and vegetables, notably potatoes, brassicas, tomatoes, apples, and gooseberries. In potatoes, tuber size is much reduced and crop yield is low. The leaves of the plant appear dull and are often blue-green in color with intervenal chlorosis. Leaves will also develop small, dark brown spots on the undersides and a bronzed appearance on the upper surfaces. In Brassicas, leaves tend to be blue-green in colour. Scorching along the outside edges of leaves is common, and leaves are often tough in texture due to slow growth. In tomatoes, the stems are woody and growth is slow. Leaves are blueish-green in colour, and the intervenal area often fades to a pale gray color and the leaf margins eventually become scorched and curl forward towards the surface. Leaves may also have a bronzed appearance and yellow and orange patches may develop on some of the leaflets. The fruits often fail to ripen evenly, and may show sharply defined, green patches near the stalks (greenback), or greenish-yellow patches, which merge into the general red color of the surface (blotchy ripening). In apples, leaves are scorched around the edges, and inter-veinal chlorosis is common. Apple fruits often have a slightly acidic or woody taste. In gooseberries, currants, and raspberries, dieback of shoots and branches is common and although the plant may produce many blossom buds in the early stages of deficiency, fruit yields turn out low and the fruits are of poor quality.
Picture by R.J. Reynolds Tobacco Company Slide Set, R.J. Reynolds Tobacco Company,


Foliar feedind in the short term will help with this deficiency. Applying Potassium fertiliser to the soil especially towards the latter part of the growing season. Applying Wood is good high potassium (and other nutrients) content, but should be weathered or composted first as otherwise it may burn plants. Acidic soil may lockup much of the available potassium in the soil making less available to the plants.

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