Utah State University Extension
This fact sheet provides step-by-step instructions on selecting appropriate soil tests, sampling, and interpreting results. Soil tests measure plant nutrient needs and soil contamination, both important aspects of sustainable urban gardening. Although many garden centers sell home soil test kits, these tests are not recommended because they were developed outside of the Intermountain West with soils that have nearly opposite conditions. Soil tests conducted in local labs may cost more initially, but will provide results specific to Utah soils and management recommendations that balance long-term soil productivity, human health, and environmental sustainability. The Utah State University Analytical Labs (USUAL) is an excellent resource for the Intermountain West.
Deciding which soil test(s) to select depends on your intent. For example, if creating a garden on land with no prior history of fertilizer or amendment (compost or manure) use, then request an Initial Urban Soil Test for soil texture, salinity, and pH. In established gardens with a history of soil amendment additions, a Routine Soil Test for salinity, pH, phosphorus, and potassium is appropriate. Lastly, if heavy metal contamination is a concern, we recommend the Total Elemental Composition (EPA 3050) Soil Test.
Stock, Melanie; Maughan, Tiffany; and Grossl, Paul R., "Urban Garden Soils: Testing and Management" (2020). All Current Publications. Paper 2116.