WHY SOIL TEST? Because it saves you money. A chemical reaction is what occurs at your plants' root tips with fertilizer, and if the soil is too acid or too alkaline your hungry plants won't be able to feed themselves.
One of the most import facts a soil test provides is the soil pH. What's pH? It is a measurement of the acidity or alkalinity of a solution, expressed as a number between 1 and 14. At the mid-point, 7 denotes neutrality. A pH number below 7 indicates acidity while a number from 7 to 14 points out alkalinity.
Most plants like to grow in soil that is slightly acid: 6.0 or so. Some plants, like azaleas, blueberries, and potatoes thrive in soil with a pH between 5.0 and 6.0.
If your soil pH is 5.5, half of the fertilizer you apply can't be absorbed by your plants.
TAKING THE SAMPLE It's really pretty simple. The only tools you need are a clean bucket and a shovel or trowel. Stand in your landscape and observe how many areas have different soil or soil that hasn't been treated like the rest of the yard.
To collect a representative sample of soil from each area, just wander about each one separately and collect five to ten four-inch deep plugs of dirt. Don't just scoop soil from on top of the earth. Stab your trowel or shovel into the ground and bring up soil from the root zone of the plants.
Place the plugs from an area in your bucket, mix them thoroughly and remove any worms, stones or plant matter. Scoop out a pint of soil, pour it into a plastic bag and label its source. Repeat for each other area.
HAVING YOUR SOIL TESTED the University of Georgia Soils Lab is a million-dollar state laboratory that will test your soil and will send you a report detailing the current levels of nutrients in the soil, its pH and specific recommendations for the fertilizers you should apply.