SOIL PH
...ssolved organic and inorganic substances. Since fourteen of the eighteen essential plant nutrients are obtained from the soil, soil pH is critical to each plants survival. The pH of the soil also affects the activity of the micro-organisms responsible for the breaking down of organic matter and most chemical transformation that take place in the soil. Micro-organism’s type and population densities changes with the soil pH. A micro-organisms activity reaches its peak at a soil pH 6.6 to 7.3. Having a high amount of microbial activity increases the availability of nitrogen, sulfur, and phosphorous in the soil. Most plant nutrients are readily available in the neutral range, although some plants need the pH of the soil to be above or below the neutral range. Nitrogen, Aluminum, Iron, and Boron are readily available when the soils pH below is 5.5; Whereas Calcium, Magnesium, and Molybdenum are more available when the pH is 7.8 or higher. The acidity or alkalinity pH a soil has several different sources. In natural systems, the pH is affected by microbiology, climate and weathering. Management of the soils often alters the natural pH because of acid-forming nitrogen fertilizers or removal of bases nutrients such as potassium, calcium, and magnesium. Some soils contain sulfur-forming minerals that can produce very acidic soil conditions when they are exposed to the air. When soils are too acidic to produce normally a farmer may need to modify his soil’s pH. A soil with a pH lower than 5.6 is considered too low for most crops. Usually the pH range for most crops is anywhere from 6 to 7. In order for to have higher yields and proper plant growth a farmer must decrease the acidity of his soil. Liming is a common method used to increase the pH of soil. The addition of lime not only raises soil pH and replaces hydrogen ions but it also puts additional amount of calcium and magnesium to the soil. Lime also increases the availability of nitrogen by hastening the decomposition of organic matter and makes any phosphorus, which is added to the soil more available for plant growth. Liming involves adding finely ground limestone to the soil. The reaction rate for limestone increases when soil temperatures are warm and soil moisture is high. If the limestone is more finely ground, the reaction is faster. The amount of limestone to apply depends on the pH of the soil along with the amount of organic matter and clay in the soil. Fertility testing laboratories make these determinations. Although in many regions of the United States, the primary concern is pH that is too low. That's why liming, which raises pH, is common in these areas. However, in other regions, particularly the arid west, soils tend to have high pH. In this case, you must acidify soil to lower pH to a more desirable level. To correct the problem with an amendment that adds hydrogen ions to the soil. Two main processes are commonly practiced in acidifying soil, both using sulfuric acid. Sulfuric acid can be applied in one of two ways: either dry application of granular sulfur to the soil or adding sulfuric acid to the irrigation water before applying it to the soil through...