In years past, gardeners or farmers tasted their soil. If it tasted sour, they knew that it wasn't good for raising crops. The same thing went for a bitter taste. But if it tasted sweet, they knew to go ahead and plant. They could also expect high yields. They may not have known it, but the sour tasting soil was too acidic to raise general crops, and the bitter soil was too alkaline to produce the yields they wanted.

If raising a garden or small farm plot is your desire there are far more accurate ways to determine whether the soil is ready to plant and more importantly to yield a decent crop. My intention in this article is to explain how to test your soil, and what to do next to correct high acidity or alkalinity or both.

Acidity and alkalinity are results of the chemical composition of the rock from which the soil is derived and the partial or complete decomposition of vegetation. The degree of acidity or alkalinity of the soil, measured in terms of pH, is known as the soils reaction. A basic indicator of soil health and fertility, soil reaction is easy to determine and, in most cases, easy to control.

Alkaline soils are most characteristic of salt marshes, western deserts, and some lime stone areas. In humid regions soil under cultivation tends to become increasingly acidic. It isn't completely understood why plants won't tolerate highly acidic conditions. One explanation is that in acid soils the chemical reaction can lock up major nutrients, especially phosphorus, making them unavailable to plants.

Too acid a soil means the bacteria which need to be present to break down organic mater cannot live. Soil that is too acidic causes aluminum and manganese to become so soluble they become toxic to plants.

Testing Your Soil

A good soil test is the surest way to determine the pH of your soil. I suggest testing the soil yourself using a pH testing meter. These are available at every major garden center. You can use litmus paper as well, but it is imprecise

• Dig a small hole in the soil. Use a trowel or spade to dig a hole 2-4 inches deep. Break up the soil within the hole and remove any twigs or foreign debris.
• Fill the hole with water. Use bottled water. Rainwater is almost always slightly acidic! Bottled water may not have a neutral pH, either, The best option is to use distilled water. Fill the hole until you have a muddy pool at the bottom.
• Inserting the tester probe into the mud.Insert the test probe into the mud. Make sure your tester is clean and calibrated. Wipe the probe with a tissue or clean cloth, and insert it into the mud. Hold it there for 60 seconds and read the machine. pH is usually measured on a scale of 1-14, though the tester may not include this entire range.
• A pH of 7 indicates neutral soil.
• A pH above 7 indicates alkaline soil.
• A pH below 7 indicates acidic soil.

Correcting Acid Soil

If your soil is too acidic it may be brought back to a favorable pH by adding limestone. Ground limestone is the commonest and safest liming material. Dolomitic is the preferred limestone because it contains magnesium in addition to calcium, thus fertilizing the soil as well as neutralizing it.

General guidelines for applying limestone are as follow: to increase the pH by one unit, spread on every 1,000 of sandy soil 30 pounds of limestone; on sandy loam, 50 pounds; on loam, 70 pounds; on clay, 80 pounds.

Spread your liming material on top of the soil after you have tilled, spaded, or plowed. Do not plow it under as it leaches down into the soil too rapidly. Repeat liming every fourth or fifth year, and do not expect a tremendous result the first year. Late summer is the best time to lime lawns and pastures.

Correcting Alkaline Soil

A slight alkalinity can often be cured with a little borax and manganese, but be guided at all times by your soil tests.

A better way to acidify soil is with naturally acidic organic materials -- oak leaves,oak sawdust, or ground up oak bark or cottonseed meal or acidic peat moss. Increasing the organic matter content can offer additional benefits. Organic matter contains natural acid-forming material and produces acids directly upon decomposition.

Obtaining a healthy yield from a garden or plot is the goal of all gardeners or farmers. High acidity or alkalinity in the soil shouldn't prevent this. Test the soil and treat it according to the findings of the test and you should enjoy healthy, high-yield crops for years to come.