Learn how to test and do a soil test and make your lawn or garden the best it can be.
What is Soil?
Soil is made up of minerals, organic matter (living and dead), air and water. Soil provides nutrients and serves as a foundation for plants. Improving your soil increases plant health and is critical to growing a lawn or garden you'll enjoy for a lifetime.
Importance of a Soil Test
For ideal plant growth, soil needs the proper pH level. pH is a measurement of how acidic or alkaline material or substance is. Soil pH signifies a plant's ability to draw nutrients from the soil. pH is measured on a scale of 1 to 14 with a measurement of 7.0 considered neutral. A number below 7 is acidic (sometimes called "sour") and above 7 is alkaline (sweet).
A soil test determines whether your soil is neutral, alkaline or acidic so you can adjust the soil to the appropriate pH level for what you want to grow. Most plants prefer nearly neutral soil with a pH between 6.2 and 7.2. Some (such as azaleas) prefer a more acidic soil. To achieve the desired pH goal, acidic soil may require the application of lime. Alkaline soils require a different type of conditioner, probably containing sulfur. A soil test also indicates which elements are missing from your soil and how much to add to remedy the problem.
Soil test kits are available at Lowe's Garden Centers. These kits will give you an immediate analysis of your soil's pH and nutrient levels. In addition, you can find testing meters that measure pH as well as moisture and light.
Your local Cooperative Extension office can test your soil sample for pH and nutrient levels (some states charge a small fee). The soil analysis usually takes a few weeks to get back to you. The analysis includes detailed results and suggested amendments specific to your region.
Home soil test kits include vials and tablets to test your soil, as well as a chart to interpret the results. With testing meters, you simply insert the meter probe into the soil and read the results. Follow the manufacturer's instructions for these home testing solutions.
To prepare a soil sample to send for analysis, you'll need a clean bucket, a garden trowel and a clean plastic (not metal) container. The steps are simple, but should be followed carefully to get an accurate reading.
Wet soil can give a false test reading. Be sure to take the sample when the soil is fairly dry. You may want to check your soil more than once to verify your results.
Soil can be tested at any time, but the best time to test your soil is in the fall or early spring. This gives you the time to make adjustments before you plant your garden, since soil corrections may take a few months to become effective.
Most native soils in the Eastern United States are naturally acidic. Alaska, Hawaii and parts of the Pacific Northwest tend towards acidic soil as well. Acidic soil is a good environment for thatch, weeds and diseases and also reduces the effectiveness of your fertilizer or herbicide.
Limestone (lime) is the soil amendment usually recommended for reducing soil acidity. Lime also is a natural source of calcium and magnesium – elements necessary for healthy plant growth. Correction of an overly-acidic soil is a long-term project that takes time to complete. Fall is the best time to apply limestone but it can be applied any time of year.
When using lawn care products or soil amendments, always follow package directions regarding proper clothing, protective equipment, application procedures and safety precautions.
Alkaline soils are most common in the central and southwestern United States, which are generally areas with less rainfall. Alkaline soil restricts plants ability to take in nutrients (such as iron).
Applying soil conditioners with sulfur or gypsum are the most common amendments. Sphagnum peat moss is an organic, naturally acidic alternative, however may be not be cost-effective to apply to large areas. Organic compost can increase soil acidity if applied regularly.
For flower or vegetable gardening, raised beds are an option. With a raised bed, you control the soil to match the needs of your crop.
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