How to Conduct a Soil pH Test at Home As a home gardener, it's important to test soil pH because certain plants have specific pH requirements and won't thrive unless the soil pH falls within a particular range. pH measures the level of acidity in the soil and it affects a plant’s ability to absorb nutrients. If the soil pH level falls outside of a plant's recommended range, all the plant food and fertilizer in the world won’t help -- the plants can’t absorb nutrients.
Technically speaking, a soil pH test measures how many hydrogen ions are in the soil. On a scale of 1 to 14, a pH less than 7.0 is acidic, 7.0 is neutral, and anything higher than 7.0 is alkaline. Acidic or alkaline soil isn't necessarily bad; it all depends on the plants you're growing.1 Most plants can adapt to soil pH ranges from 6 to 7.5, but some plants have distinct requirements. For instance, blueberries require acidic soil in the range of 4.5 to 5.5 to produce berries while lavender tends to do best in alkaline soil about 8.0.