Soil pH is extremely important for optimal plant growth.
Very acidic soil (pH 3.0 – 5.0)
Most plant nutrients, particularly calcium, potassium, magnesium and copper, become more soluble under very acid conditions and are easily washed away
Most phosphates are locked up and unavailable to plants below pH 5.1, although some acid tolerant plants can utilise aluminium phosphate
Acid sandy soils are often deficient in trace elements
Bacteria cannot rot organic matter below pH 4.7 resulting in fewer nutrients being available to plants
Alkaline soil (pH 7.1 – 8.0)
Phosphorus availability decreases
Iron and manganese become less available leading to lime-induced chlorosis