SOIL ACIDITY

Wairarapa Times-Age, 26 August 1938, Page 3

SOIL ACIDITY

RELATION WITH PLANT GROWTH. It is commonly assumed that an acid soil is not in a suitable condition for the successful growth of crops. Soil acidity, however, is a relative term, in the light of the knowledge that some crops plants can successfully support a reasonable degree of acidity and be capable •of producing a profitable yield, when some other species may be very injuriously affected. The potato is not at its best in a very alkaline soil containing a high percentage of lime, which may induce ordinary scab, but it does particularly well in a some* what acid soil, whereas the turnip and its allies are extremely liable to the disease, finger-and-toe, when grown in acid soils, so much so that a heavy dressing of lime t is recognised as the most valuable means of rendering such soil fit to grow the same species again, and free from the disease. It is wellknown td expert gardeners, who commonly deal with a far wider range of species than are found on the farm, that many plants which they grow are intolerant of lime, while many others equally demand the presence of lime in quantity if they are to be raised with success. Generally speaking, the ordinary economic crops of the farm and garden are best grown in a nonacid soil. In this connection it is to be borne in mind that most crops remove a proportion of lime from the soil in which they grow, and this in itself is an indication how very necessary it is to add lime to the soil at regular 'intervals. Another thing that must also be Borne in mind is that the application of certain fertilisers may have the result of decreasing the amount of lime through the formation of soluble lime compounds which are washed out of the top soil in the drainage waters. It has often been stressed in these columns that lime is not only of great value in itself but that it also assists the usual fertilisers to more properly carry out their functions.