1: Clean the surface soil layer’s all organic impurities which may affect the test results, such as the leaf or the root.Step 2: Clean the probe tip with wipes or abrasive cloth.Step 3: Insert the probe tip in the testing soil, the probe tip should LEVEL with root.Step 4: Reading the result when the value is stableStep 5: Testing it again on the different place of the testing soil, then calculate the average value.
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