Definition - What does Acid Soil mean?
Acid soil is soil with a pH value of less than 5.5 throughout the year. Soil acidity occurs naturally but can also be created with the use of chemicals. Acid soil created by metal toxicity (like Aluminum) can affect root growth by:
- Decreasing the root's ability to access essential nutrients
- Increasing the negative impact toxic elements may have on the vine
- Decreasing the vine's production and overall water usage
- Affecting essential biological soil functions, like nitrogen fixation
- Making soil more vulnerable to structural changes like volume decline and erosion
WineFrog explains Acid Soil
PH levels are generally scaled between 0-14; soil pH is measured the same say. On the soil pH scale, 0 represents being acidic in nature and 14 being alkaline in nature. A pH of 7 is considered neutral. Most plants need a pH level between 6 and 7.5, because that’s when phosphorus is most prominent in the soil. Phosphorus is one of three nutrients required by plant life to help with fruit set and plant bloom. Phosphorus is soluble, meaning it dissolves in water and is consumed by the vine’s roots.
Acid soil naturally occurs in locations prone to higher rainfall though the levels are completely dependent on the landscape geology, clay mineralogy, soil texture and buffering capacity. While soil acidification occurs naturally, it is increased by specific agricultural practices, like using nitrogenous fertilizer or removing plant material from the soils. Leaching (where key nutrients, like potassium, magnesium and calcium are washed out of the soil) due to excessive rainfall or irrigation causes an imbalance in the pH levels since these nutrients are alkaline in nature.