Soil Application Notes

Benefits of the IQ ISFET pH meter:

	Rugged- no glass to break
	Portable- can go anywhere you go to monitor your soil pH levels
	Easy to use- no maintenance and stores dry
	Easy to clean- with a toothbrush and detergent
	Long-lasting- 15,000-25,000 tests typically

Soil pH measurement is important because it is a detector of different chemical activities occurring in the soil. As a result of pH monitoring, one can make decisions about the types of plants suitable for a location, the need to change soil pH (up or down), and the proper availability of plant nutrients in the soil. As the amount of hydrogen ions in the soil goes up, the soil pH drops, thus becoming more acidic. PH is measured on a scale of 0 to 14. A pH of less than 7 means the soil is acidic. A pH of over 7 means the soil is alkaline or basic.

Soil pH has a large effect on the solubility of plant minerals or nutrients. Fourteen out of seventeen essential nutrients are found in the soil, but a nutrient must be dissolved in the soil solution before a plant can use it. Most minerals and nutrients tend to be more soluble in acid soils than in neutral or slightly alkaline soils. As soil pH decreases, nutrients, like phosphorus, usually decrease in availability due to precipitate reactions with aluminum and iron, but plants can affect their own microenvironment and can often grow well over a range of pH. Generally, many plants can thrive in a pH range of 5.5 to 7.5. Specific plants, like azalea or pine seedlings, require a lower pH. These plants are iron deficient so they need low pH to help in the absorption of iron from the soil. As soil pH rises above 6.5, the micronutrient, manganese, can become the limiting factor to plant growth. Phosphorus, copper and zinc also decrease at high pH levels. You can see why pH monitoring with the reliable IQ rugged handheld meter is important to keeping soil nutrient-balanced.

Soils seem to become more acidic through the following processes: rainwater takes away basic ions like calcium, magnesium, potassium and sodium; carbon dioxide of decomposing organic matter dissolves in soil water and forms a weak organic acid; and the formation of organic and inorganic acids, like nitric and sulfuric acid, from decaying organic matter and oxidation of ammonium and sulfur fertilizers.

Liming of soils

Lime can be added to acidic soils to increase pH. Lime replaces the hydrogen ions and raises pH, eliminating most of the problems related to acidic soils, while providing nutrients like calcium and magnesium to the soil. Lime also makes phosphorus more available for plant growth and increases nitrogen availability by speeding up the decomposition of organic matter. Common liming materials are inexpensive, easy to handle and leave no harmful residue in the soil. Liming materials are calcic limestone, dolomitic limestone, and wood ashes. It is important to monitor soil pH with the IQ rugged handheld meter in order to determine the correct amount of lime and solve the soil acidity problem.

Sometimes one needs to acidify the soil, to lower soil pH. If high soil pH is a natural condition, not much can be done to permanently lower the pH. Treatment with sulfur will lower the pH for a couple weeks, but it will increase again. It is often better to grow plants that are adapted to the natural soil pH range, instead of having to constantly maintain the soil pH with no definite results. In situations where high soil pH is caused by human activity, like over-liming, one can lower the pH with applications of sulfur. Accurate and easy pH measurement is guaranteed with the IQ rugged handheld meter helping you to reach the proper soil pH in which your plants will thrive.

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