ON THE LAND

Nelson Evening Mail, Volume LXXI, 10 February 1938, Page 10

ON THE LAND

NOTES AND COMMENTS

USE OF POTASH ESSENTIAL FOR PLANT LIFE Potash is one of the substances essential for plant life, says Mr H. W. Hesse, Instructor in Agriculture and supervisor of agricultural instruction to the Wellington Education Board. The following effects can be directly attributed to a deficiency in the supply of available potash present in the soil: — (1) The crops grown are of a poor and dull colour. Mangel leaves tend to die at the tips. (2) There is a loss of efficiency in starch making. Without potash, plants are unable to manufacture stafeh from the carbon-dioxide gas present in the ; air. All green plants must undertake starch formation in order to obtain the food supplies of carbon compounds necessary for their growth. And potash is especially required for crops which produce a large quantity of starch and sugar. Examples of these crops are mangels, potatoes, cereals and maize. (3) Potash deficiency is evident in crops with stunted grain production. Potash has a marked effect on grain and seeds, increasing the weight harvested. (4) Potash-starved plants are the first crops to suffer in a bad season. And they are the first to succumb to disease. The general tone and vigour of the plant are dependent on the available supply of potash. It has been noted; that rusts on cereals and grasses, leaf rot on mangels, blight on potatoes, and many other fungoid diseases are all I more prevalent in potash-starved crops | than on those well supplied with [ potash. I ADVANTAGES OF POTASH MANURING I In addition to counteracting the illeffects enumerated above. potash manuring produces the following advantages:—

(1) Clovers and other leguminous corps, such as lucerne, are potash lovers. And they need a sufficiency of available potash to give remunerative results. (2) Potash salts increase the production of starch and sugar in plants. (3) Potash has a remarkably good effect on onions afld leeks. It increases the yield very considerably, improves the soundness of the sample, and checks the tendency of the crop to become ‘bull-necked.” (4) Potash applied to fruit trees has a decided effect on the early ripening of the fruit. <5) There must be an adequate supply of potash in the soil to obtain the full value from applications of phosphatic and nitrogenous manures. ( 6 > Pastures are sweetened by the use of potash It tends to destroy mosses, and to suppress flat weeds. (7) Potatoes grown with potash afe said to be less liable to disease, and they are almost invariably of better quality than where farm manure has been used. (8 1 The crops most responsive to the action of potash manures are potatoes, peas, beans, clovers, vetches, mangels, and turnips. These crops are less capable than others of utilising the natural potash of the soil.