(6)Kiwi Phils Gardening Corner - 'ph' explained.

[Kiwi Phil]

In a post way back, some one said they had their soil tested for ph, and added lime (I think) and their garden has just got better and better.<br /><br />To test soil ph is easy. Hardware/gardening centres should have simple ph soil kits, or maybe they will do the test on the sample you take them.<br /><br />Alkaline soils are "sweet". <br />Acid soils are "sour".<br />Values of pH 7.0 indicate neutral.<br />Soils above pH 7.0 are alkaline. <br />Soil below pH 7.0 acid .<br /><br /><br />To make an acid soil more alkaline add lime. Slightly acid soils can be made more acidic by adding peat, iron sulphate or flowers of sulfur. It is hard to lower pH in an alkaline soil.<br /><br />Changing pH is not an exact science and most plants have a wide tolerance, certainly to within 1 full pH point. <br />So:<br /><br /><br />.<br /> pH can affect the availability of nutrients to a plant. <br /> pH can affect the absorption of nutrients by plant roots <br /> pH values above 7.5 cause iron, manganese, copper, zinc and boron ions to be less available to plants. <br /> pH values below 6 cause the solubility of phosphoric acid, calcium and magnesium to drop. <br /> pH values between 3 and 5 and temperatures above 26OC encourage the development of fungal diseases. <br />pH is not as critical as most believe. The main point is to avoid extremes in pH. Plants grow on soils with a wide range of pH. For most plant species there is an optimum pH in the region of pH 5 to pH 6<br /><br />Lets imagine you ate nothing but "lettuce" all and every day. Your health will suffer pretty badly. You need a wide range of chemicals to sustain a healthy disease free body. Well it is the same for plants. If the ph is way out, then there are a lot of chamicals they can not get, hence, like you, their health suffers.<br /><br />It is a really easy test (ph), and the cost for adjusting your gardens ph (if needed) is minimal, and the results are woth the effort.<br /><br />Cheers<br />Phillip