SOIL ANALYSIS

BY GEORGE EDGAR

          Did you have trouble with a particular area of your lawn and/or garden the past year? Are some of your plants just now growing the way they should? Are you planning to plant a new flower garden or vegetable garden? Are you going to put in a new lawn and/or shrub or tree this fall and wonder if the soil needs to be amended or improved so that it will grow to its maximum? If you answered yes to any of the above questions, now is a good time to get your soil analyzed so you get the results back as soon as possible. Fall is the best time to amend your soil so it is ready for planting next spring or possibly later this fall.

          I suggested you get a soil analysis as this is more than just a test for pH and maybe a few other chemicals. A complete soil analysis could include: Organic matter, exchangeable Potassium, calcium, Soil pH, Cation

Exchange Capacity (CEC), Nitrate Nitrogen, Excess Lime, Available Phosphorus, Magnesium, Hydrogen, Buffer Index, Soluble Salts, and Sodium. Sarah Browning, Extension Educator for Lancaster County and a frequent panelist on “Backyard Farmer” recommends tests for “residual nitrogen, phosphorus, potassium, organic matter, cation exchange capacity, (CEC), and soil pH, along with recommendations for soil amendments for you landscape based on the plant types you indicated on the submittal form.” (1) If you are unable to read and interpret the results, visit your local Extension Office and they will be happy to help you.

          There are five soil testing labs in Nebraska. Just Google “Soil Analysis Labs in Nebraska and you will find them along with their address and phone number. All have good web sites to help you including detailed listing of the tests they can do, costs, and how to take a soil sample. Follow the directions they give you.

          You will want a separate test for your lawn, for your vegetable garden, for your flower garden, and for planting your fruit trees, and other trees. The lab will ask you what you are going to grow. It maybe stated as asking for your “crop” as they primarily do soil testing for agricultural products. When you collect and send in soil samples do NOT use a metal container as the metal will contaminate the sample. A plastic bag or glass container works best. Most also have a “Soil Test Kit” available that you can order. One other suggestion: take samples from different parts of your garden and/or lawn. Remove any organic matter such as such as grass or weeds, and mix the samples together. The lab will need only about 1 pint of soil from each location.

          One test many may not understand is the SOIL CATION EXCHANGE CAPACITY (CEC). According to the Random House Second Edition Unabridged Dictionary the Exchange Capacity of your soil is a measure of its ability to hold and release various elements and compounds. We are mainly concerned with the soil’s ability to hold and release plant nutrients.

          Simply, “The Cation Exchange Capacity of your soil could be likened to a bucket: some soils are like a big bucket (high CEC) some are like a small bucket (low CEC). Generally speaking, a sandy soil with little organic matter will have a very low CEC while a clay soil with a lot of organic matter (as humus) will have a high CEC. Organic mater (as humus always has a high CEC. With clay soils, CEC depends on the type of clay.”(2)

Copyright 2016

Resources:

(1) March 2011, Sarah Browning, Extension Educator, University of Nebraska-Lincoln in Lancaster County. This resource appeared in the LincolnJournal Star Newspaper Sunday Edition.

(2) The Ideal Soil:A Handbook for the New Agriculture, 2014 Edition, from SoilMinerals.com by Michael Astera, Chapter 2.