Step 3: Insert the probe tip into the test soil, the probe tip should be LEVEL with the root. Humidity range: 1-10 (1-3 dry, 3-7 dry, 7-10 wet). pH range: 3.5-8PH (3.5-7 acidic, 7-8 alkaline). Step 5: Test it again in the different place of test soil and then calculate the average value.
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