By soil conditioning we are referring to the physical and chemical condition of soil and methods of changing this to a structure which will be more suitable for growing a specific plant. It is important to know if the soil is acid, neutral or alkali, this characteristic is commonly referred to as the pH of the soil. This is measured on a scale of 0-14 units with the neutral point being at 7. Soils with an acid pH are recorded as being less then 7 and alkaline soils higher then 7. The majority of soils are in the pH range of 4.5 to 7.5, these are defined as follows: - 5.0 or less - acidic 5.5 to 6.5 - slightly acid 7.0 - neutral 7.5 - slightly alkaline The pH of soil can be measured by an electronic meter or probe or by use of chemical indicators such as a soil test kit. Equipment for both these methods is widely available. In the laboratory pH can be determined very accurately by use of an electronic pH meter. It is a good idea to check the pH of soil regularly, and occasionally obtain a complete check by a professional soil analyst.