Soil Nutrient Testing
On February 28, 2019, the Agricultural Waste Control Regulation was replaced by the Agricultural Environmental Management Code of Practice. This page is being updated to be consistent with the new regulation.
A major reason for soil testing is to evaluate soil fertility (the ability of the soil to provide plants with nutrients).
Other reasons include evaluating physical properties (texture) or chemical properties (soil pH ), and many laboratories that offer soil fertility testing services also analyze these properties in addition to analyses for plants, manure, or water.
Soil fertility testing involves 3 steps:
1) Take soil samples and prepare them for analysis
2) Get the soil samples analyzed
3) Interpret soil analysis results (for fertilizer recommendations)
When the soil is sampled is critical to interpreting soil tests for N. For deciding what rates of N to apply, interpret the pre-sidedress nitrate test (PSNT, mainly corn) to make mid-season decisions about nitrogen fertilizer. Interpret the post-harvest nitrate test (PHNT, all crops) for feedback about nitrogen management in the year of sampling.
Phosphorus (P) and Potassium (K)
Different laboratories use different methods to determine soil test phosphorus (P) and potassium (K). Convert soil test P and K values to “Kelowna method” values to compare results of different methods. Monitor and compare results over several years; samples should be taken at the same of the year to be comparable. Alternatively, use the information below to find soil test-based fertilizer recommendations that you can adjust as you monitor results:
- Interpretations for Soil Test Phosphorus and Potassium: Guideline for Southern British Columbia (PDF)
Other Nutrients – All regions of B.C.
Phosphorous (P), Potassium (K), Magnesium (Mg), Sulphur (S), Boron (B), Copper (Cu), Zinc (Zn)