Why Test Your Soil?

A good soil provides adequate drainage, moisture retention and proper fertility.In order to have good, healthy, productive plants; you must start with fertile, healthy soil. Good soil retains water, releases nutrients and drains well.  It must contain adequate nutrients, optimum pH and organic matter to be healthy and fertile.

Guessing about additives for your lawn or garden usually means too little or too much fertilizer gets added.  Too little fertilizer may result in unhealthy plants.  Too much is wasteful and can threaten our lakes and wetlands.  Also, soils vary within the state, your neighborhood, and even your yard.  What may be good for you neighbor or brother’s lawn or garden may not be right for yours.

Don’t guess or take someone else’s recommendations.  Find out what your soil needs.  Take a soil test. 

Soil Test Results

What type of soil do you have in your garden?A soil test will tell you what nutrients your plants or lawn need and will recommend the amount of fertilizer (N-P-K) to add to your soil. The N stands for nitrogen.  Nitrogen encourages fast, green growth.  The P stands for phosphorus.  Phosphorus stimulates root development, rapid growth, and quality flowers.  The K stands for potassium and  promotes disease resistance, strong stems, and winter hardiness.

A soil test  will  also tell the current pH of your soil.  Soil pH is a measure of soil acidity.  Nutrient availability is influenced by the pH of the soil.  Plants need an optimum pH to grow and be productive.  Acidic soils have a pH lower than 7.0. Neutral soils have a pH of 7.0.  And soils with a pH above 7.0 are called alkaline.  Compost is one way to add organic matter to your soil.Most plants will grow adequately up to a soil pH of 7.5. Some plants, such as blueberries and azaleas, love acidic soil while other plants, such as tomatoes and carrots, prefer alkaline soils.

The results of the soil  test also include an analysis of the amount of organic matter in your soil. The amount of organic matter is important because the more organic matter you have in your soil, the better the water holding capacity, drainage, and tilth of your soil.  To increase the organic matter level in you soil; you can add materials such as  manure, compost, or peat moss. 

Testing Your Soil

A soil test will evaluate your soil for many factors.You can take soil samples any time the ground isn’t frozen.  You should get your soil tested by any state certified soil-testing facility.  For your convenience, you can get your soil tested through your county UW Extension office which uses the UW Soil and Plant Analysis Laboratory in Madison.  The following information should be taken into consideration when taking a soil sample to be used for a soil test: 

Call your county UW Extension office for more information on soil testing. 

Ann Wied, University of Wisconsin – Extension, Waukesha County

Additional Information:

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