People often ask me whether they should test their soil for its pH.  A pH reading tells whether the soil is naturally acid, alkaline or balanced and neutral. You can do this yourself if curious by purchasing a small soil testing kit which will come with strips of chemical impregnated paper that will change colour when dipped into the moisture from the soil.

If you determined your soil is already a dark crumbly loam, the chances are your soil is neutral. If your soil holds a lot of water it can become acidic but the chances in the Kootenays are not likely for the majority of our natural soils are on the alkaline side. Many people associate evergreen vegetation with acidic soil but in the Kootenays the soil remains alkaline. It will take a lot of evergreen foliage and water to change it. The difference between the Kootenays and the Coastal climate is elevation, type of vegetation and amount of precipitation. This affects the soil pH. It is true that with enough evergreen foliage the soil pH may change slightly but it would require massive amounts.

Plants will grow in acid and alkaline soils and some plants have a preference for one or the other. What plants do not like is an extremely acid or alkaline soil. The chances of finding that situation is unlikely. The reason some people wish to know and change the pH of their soil is either because they wish their soil to be better balanced or they require a certain pH to grow a particular type of plant.

Whatever the nature of your soil, the amendment procedures are the same. A water hog soil is more likely to be slightly acidic so better drainage is required – add sand. A soil that does not hold moisture and drains too quickly needs something to hold the moisture – add humus and or regular soil.

 For Hydrangea, Azalea and Rhododendron lovers, these plants generally prefer a slightly acidic soil and achieving a change even with amendments is very difficult. We are lucky that we now have many Hydrangeas bred to do well in our generally alkaline soil but Azaleas and Rhododendrons are still tricky. Think about the provenance of these plants and you will understand why they prefer slightly acidic soil. It is always very useful to know where a particular type of plant grows naturally because that will tell you the type of conditions it favours.

Generally a pH of close to 7 is recommended for a good loam.

pH scale from Sciencenotes.org

There are boxes of artificial soil amendments such as Sulphur, Aluminium or Ferrous Sulphate which can be added to the soil to help keep these plants healthy. However natural precipitation will quickly undo any changes you try to make. In my experience it is better to grow plants that thrive in what you have. There are Hydrangeas which will grow well in this zone three mountain climate with slightly alkaline soil. Azaleas and Rhododendrons will usually struggle no matter what you do. In this grouping of less cold tolerant, acid loving shrubs and trees are Magnolias which surprisingly are more tolerant of a drier soil. They actually prefer a well-drained soil but do still prefer a slightly acid one. However I know of several Magnolias growing well in our Zone three area. When you think of China and areas where these plants thrive, the difference is usually humidity and temperature. ‘Star’ Magnolia is one to try. It is small but will be covered in white starburst flowers in spring. This magnificent yellow flowering Magnolia grows in a friend’s garden in Cranbrook.

‘Star’ Magnolia left and ‘Yellow Bird’, right, both growing in Zone 3

I believe the time for serious soil testing only comes if the soil you are dealing with was once a gas station, or had an oil tank on the property or was an old industrial site. Many old properties in this area had oil tanks for heating their premises and if they have been left untouched could leak and pollute the surrounding soil. This is highly unlikely but it happens. The smell test will frequently alert you to this type of problem. If you do have this problem, depending on its severity, you may need to have the soil removed.

The best thing a person can do to keep their garden soil healthy and balanced is to continually compost their vegetable waste. This will be tackled in a later article but it is never to late in the year to start a compost, bin, box or pile. Just begin with leaves. A garden can rarely have too much organic material.