Urban gardeners, test your soil.

Soil Test


            Do you know what is in your soil?  Not the generic answer: Earthworms, water, sand, silt, clay.  I am talking about the specific amounts of each nutrient.  The microbiological life that is teaming or suffering within the soil?   Without a soil test, it is impossible to know these answers.

            A soil test provides precise and accurate measures of the essential nutrients- nitrogen, phosphorus, potassium—the state of the soil, including the soil pH.  Soil pH is the vital information received from the test, and pH plays a crucial role in nutrient availability to plant roots, nutrient run-off, and microbial efficiency.  You get the pH right, and other things tend to work.

 More extensive tests can even test the microbiological in your soil and the levels of secondary and micronutrients- Zinc, iron, sodium, sulfur, magnesium, manganese, and copper. Not only do these tests tell you your soil levels, but they also give you fertilization recommendations to get your soil to optimal levels of these nutrients. How can we know what to add to the garden soil if we don't know what is already present? 

            Some people don't realize that adding excessive fertilizer can be even worse for your garden production than under-fertilizing.  Excessive amounts of specific nutrients can lead to a term known as a nutrient lockout.  Nutrient lockout occurs when a plant cannot readily absorb the present nutrients. The nutrient lockout can be avoided by following the fertilization recommendation provided by the soil test.

          How do I get a soil test? Who administers these tests? What do I need to do? Easy, collect a sample and submit it to an A&M, agricultural and mechanical university, and they will do the rest.

Sample Areas

You collect a sample from everywhere you are interested in having tested.  You must examine all the areas, and do not assume that all areas of the yard are the same.  There can be variations between front yard, back yard, planting bed, garden, etc.

Collecting a Sample

  1. Remove mulch, decomposing matter, grass, leaf matter, etc.,  from the top of the area you're testing. 
  2. Collect a soil sample from 6" depth. Repeat 5-10 times for the testing area and combine the soils from the same area.
  3. Allow moist soil to air dry before placing 1-3 cups in a heavy-duty plastic bag.
  4. Mail to Agriculture extension office and sit back and wait.

It is that easy to get your soil tested and receive a proper fertilization recommendation.  Test your soil every few years to ensure you are on the right path.  Even if you are an organic gardener, testing the soil is still essential.


Here is a list of where to get your soil tested state by state. If the links are dead, enter "soil test" into the search bar






Older Post Newer Post

Leave a comment