Recommended Soil & Water Tests
Every soil testing lab offers its own specific analysis and recommendations, and you can send soil sample to the lab of your choice. I frequently recommend Regen Ag Lab in Nebraska and Logan Labs in Ohio as great places to start. The table below lists the soil and water tests I recommend. I may update the list as my knowledge evolves. For a cost-effective baseline nutrient assessment, I suggest either the Ag-Dyn 3 test from Logan Lab or the Complete plus the hot water extract for Molybdenum.
If you want to gain a more comprehensive understanding of your farm or property as an ecosystem, I recommend running the Total Nutrient Digest, Complete, Haney SHA, and Complete Water Analysis from Regen Ag Lab. This set of tests will reveal the nutrients in your parent material and organic matter, whether your irrigation water will affect nutrient availability, and how nutrients will cycle and if your soil is biologically active. These four tests provide a good overview of the chemical aspect of soil health and insight into the biological aspect. Of course, there’s more to uncover, and we will use the information you provide in the intake form and other sources.
My focus is not on creating a perfect soil report, but rather on optimizing soil function. The baseline information will enhance the overall picture of your farm.
Key Technical Similarities & Differences
General Ideal Time
Suggested lab and test to run
Are you creating your project's baseline? Run these.
Standard Soil Test
Nutrient & Mineral Availability
Snapshot in time, weak acid extraction, shows available nutrients & minerals, useful for making soil fertility amendment recommendations
At the beginning of a project or garden. Fall is ideal, but spring is fine.
and/or Haney SHA
Total Digest or Acid Extractable Totals Test
Strong acid extraction, provides insight into soil's deep reserves, long term nutrient assets and weaknesses
At the beginning of a project or garden. Only needed once per soil type
Regen Ag Lab - Total Nutrient Digest
Saturated Paste Test
Shows minerals & nutrients in soil solution, useful for growers/soils that rely on soluble nutrition
Early season in-field, anytime of interest in soilless media, just before fruiting and crops transitions
Haney/Soil Health Analysis
Soil Health and plant available nutrients
Dual extraction process, mimics plant produced acids, biological indicators, shows soil health score, is becoming useful for making soil fertility amendment recommendations. Can be ran instead of a standard soil test.
During the most biologically active phase of the season, like early summer
Phospholipid Fatty Acids (PLFA)
Soil Health, Microbial Biomass, relative abundance of slow growing microbes
Estimates living microbial biomass in soil, provides information on different functional groups of organisms, F:B ratio is a good indicator of function
When the grower wants a broad objective qualitative and quantitative biological soil health baseline, when experiencing nutrient tie-ups or exceptional plant health
Soil Health, Microbial Processes in Nutrient Cycling, diversity of community “who is really there”
DNA extraction. Measures microbial diversity, function and processes involved in nutrient cycling
Anytime, this test extracts DNA for active and dormant biology
Soil Health, Course count of bacteria, protozoa and fungi
Subjective qualitative and quantitive soil biological assessment. Accuracy will vary with the practitioners skill and knowledge.
During the growing season or once soils warm
Water Analysis - Packages
Irrigation water nutrient assessment
Water test for nutrients, pH, and other variables like carbonates and bi-carbonate that can antagonist soil nutrient availability to plants
At the beginning of a project, anytime a water source changes or their is issues with nutrient tie-up