The pH scale is a scale that measures how acidic something is and ranges from 0 (Very acidic) to 14 (Very alkaline), where pure water is slap bang in the middle with a pH of 7 meaning it is neither acidic nor is it alkaline.
So as shown in the chart above if the pH is greater than 7 it is alkaline, and below 7 it will be acidic. The scale then just tells us how acidic or alkaline a substance is.
The traditional method of testing – and many of you will have done this at school was to use litmus paper – if it turned red it was acidic, and blue it was alkaline. There are of course many other more accurate tools for testing pH too.
When we are talking about soil acidity we are usually talking about a range between pH5-pH8, so the soils will be slightly acidic or alkaline – if it is much beyond these figures we are unlikely to be able to grow much!
Soil testing kits are relatively cheap to buy and there are several on the market ranging from disposable kits to more expensive reusable tools, and it’s well worth testing your soil before planting, as the more you understand about your soil, the more you will be able to get out of it.