The concept of soil pH is not complicated.  Most soils are typically in the 6.5 to 7.0 range, with 7.0 considered neutral on the 0 to 14 scale.  As the pH drifts one way or the other, complexes form in the soil that render specific nutrients unavailable to plants.  A typical example is a tree that exhibits yellowing leaves near the end of the stems.  This problem is observed most often in alkaline soils (those above pH 7.0).  The problem results from the lack of iron available to the tree at higher pH levels.

What can you do if you live in an area plagued by a high pH level?  The easiest solution is to plant trees that are adapted to those conditions.  Here is a list of the top five choices in no particular order:

1. Catalpa
2. Lilac (technically a shrub)
3. Redbud
4. Green Ash
5. Bur Oak

Certain regions of the United States are known to have higher pH levels in the soils.  For example, in the area of Idaho where I reside the pH is known to be alkaline due to the large amount of limestone associated with the Rocky Mountains.

Home soil pH kits are available at your garden center.  To have you soil professionally tested, contact your local Cooperative Extension office.  The number is usually located in the government section of your phone book.

Happy Gardening!