Soil pH measures acidity or alkalinity on a scale of 1–14, with 7 being neutral. Most garden plants prefer a slightly acidic pH of 6.0–6.8. When pH is off, plants cannot absorb nutrients properly even if those nutrients are present in the soil. Acid-loving plants like blueberries, azaleas, and rhododendrons prefer pH around 4.5–5.5. We carry soil amendments to raise or lower pH as needed.