IMPORTANCE OF LIME

Timaru Herald, Volume CXXXIX, Issue 20065, 23 March 1935, Page 15

IMPORTANCE OF LIME

UNLOCKING FERTILISING SUBSTANCES It is seldom realised what a very important part lime plays in the fertility of the soil. The farmer is inclined to look upon it as fulfilling a role of the same nature as the well-known fertilising agents, phosphate, nitrogen and potash. However, lime has really an indirect action on the soil, but the part it plays in making the soil suitable for plant growth is in no degree less important. The agricultural scientist tells us that lime affects the soil mechanically, chemically and biologically. By its mechanical action is meant that lime renders the land more workable. more particularly in regard to the stiff clay soils. It has long been known what a difference an application of lime to stiff clay will make in the task of the ploughing. This is because the lime affects the texture of the soil considerably by causing the fine clay particles to come together in larger particles, i.e., to cogulate, thus making the soil friable, or, in other words, easily crumbled. Thus lime has the power of “lightening” heavy soils, thus rendering them the more easily ploughable. More important than the mechanical action, however, is the chemical action of lime. Lime possesses the power of unlocking the inert fertility of the soil. There may be fertilising substances present in abundance in the soil but they may not be in a form available to the plant. Lime breaks down these substances. Furthermore, it helps to decompose vegetable matter which means the liberation of plant food. This accounts for the beneficial action of lime on peaty soils which, of course, are rich in organic matter. Lime, then, is an agent that is able to change the nature of fertilisers so that they become available to the plant. Lime, also overcomes that condition of sourness in the soil, sweetening it and preventing the formation of poisonous compounds. By its biological assistance we mean that lime encourages the bacteria in the soil, the nitrogen fixing bacteria and other bacteria that attack the remains of animals and plants. Thus, briefly, it is shown why lime is so essential and how its inclusion in the soil makes for an increased supply of plant food and checks any acidity that might have a detrimental effect.