Many experienced gardeners develop a knack for knowing the condition of their soil by observing plant growth, soil texture and the emergence of specific weeds. New gardeners, or gardeners starting a new bed in unfamiliar soil, benefit from testing the soil for vital nutrients and pH levels. The resulting soil analysis provides direction for amending soil to create nutrient-rich soil that supports vigorous growth.
Soil test kits, available in hardware or seed stores, are inexpensive and offer the convenience of immediate results. Testing requires placing a small sample of soil in vials prepared with the testing material. The reaction of the soil to the chemicals used causes color changes in the water, which is then matched to a chart to determine the nutrient level and pH of your soil. The kit contains direction for amending the soil to attain an appropriate balance of nutrients and to adjust pH, but does not address soil structure. The amount of organic matter and the ratio of soil particles (like sand and silt) determine the structure of your soil.
Cooperative Extension Services
Your local cooperative extension offers soil testing for a reasonable fee. This involves gathering the appropriate sample and mailing or delivering the sample to the extension office. The soil is then analyzed and a written summary of the condition of your soil is prepared. Procedures for amending the soil are included in the report. Results from a soil test by the extension office generally provide more accurate results and specific instructions for amending and improving soil structure, nutrient levels and pH.
Home soil tests provide a general overview and description of best practices for maintaining rich soil, but may not provide adequate detail to determine the best procedures for adjusting the soil. Results from the extension office include detailed explanations and specific adjustments based on your soil's available nutrients and structure.
Amending the soil following the recommendations may not show immediate results. Most soil amendments require time to process and improvements in plant growth and production may not be realized for several months. When possible, testing the soil and making the necessary adjustments in the fall for spring planting is desired.
Soil is in a constant state of flux. Nutrients can be leeched away by rain or drain away from raised beds, altering the balance of available nutrients. Soil may change between the time you take the sample and results are returned. The more time that passes between taking the sample and viewing the results, the greater the chance of changes in the soil.