Understanding Soil pH and its Importance

Why do you need to know this? Because many plants are quite fussy about pH and will either fail to thrive, or even die, if you plant them in the wrong conditions.

Gardening without knowing whether your soil is acid, alkaline or neutral is like playing golf wearing a blindfold - sometimes you will hit the ball but more often than not you will miss!

In gardening terms, this means wasting your money buying plants that are never going to do well, and then wasting your time and effort planting them only to watch them slowly perish... and let's face it, it's hard to enjoy a garden full of sick and dying plants!

What is Soil pH?

However, some plants, such as rhododendrons, are ericaceous, or acid loving, and need an acid soil to thrive, whilst others, including saxifrages, are calcicoles, or lime lovers, and need an alkaline soil to do well. (Just to confuse you, note that ericaceous plants are also sometimes known as calcifuges, or lime haters!) Such plants are adapted to extreme soil pH ranges and their growth will suffer if they are planted in soil with the wrong pH level.

It is possible to raise the pH of acid soils by adding lime, or to lower the pH of alkaline soils by adding sulphur, but this is costly over a large area and the results are temporary.

If you find you have a very acidic or alkaline soil, the easiest solution, as always, is to work with what you have by choosing from the many delightful lime tolerant or acid loving plants.

If you have set your heart on a particular plant that needs different soil conditions, grow it in a container filled with an appropriate compost or soil mix.

As a rough guide, chalk soils and those in limestone areas will be alkaline whilst more peaty soils will usually be acidic. However, it is not always obvious and it is certainly worth buying and using either a soil pH test kit or pH meter to find out for sure.

Both DIY pH test kits and meters are inexpensive and give good results. The pH meters can also be used time and time again making them very cost effective. There are a number of reasonably priced soil test kits and meters on the market and, as well as telling you the pH, some will also test for the levels of important nutrients in your soil.

The Next Step...

If you need more information about soil you can get an overview of the subject, together with links to other soil-related pages, by returning from 'Soil pH' to 'Healthy Garden Soil'.