How to Test Soil for Tree Planting

There are a few reasons to plant a tree: landscaping, shade, food, the environment or all of the above. However, to ensure the health of the tree, there are several things to consider. Look at the location, where its branches and roots will be in correlation to buildings and overhead or underground lines.

The first thing to consider when planting a tree is the soil. It is simple to find out if the location where you are thinking of planting has proper drainage. The proper pH in the soil is a factor that helps to keep your tree alive for many years.

To learn more about your soil, you will need the following:

• Clear plastic container that holds about 2 cups of water (or a soft drink bottle with a lid, that has been rinsed well)


• Water hose, large bucket or other container to carry water


• Water


• Trowel


• Shovel


• PH testing kit

1. You can find out what kind of soil you have by filling the clear plastic container with water, then adding about half of an inch of soil to the water. Stir or shake, then allow the soil to settle once again. Clay and organic materials will float; sand will remain at the bottom.

2. To find out whether the drainage where you intend to plant is adequate, a hole must be dug. If you will be planting in a grassy area, you can preserve the patch of grass where the hole will be dug, just in case the drainage test shows planting in this location is not wise. Carefully use the shovel to press into the soil repeatedly, to cut out a circle that is 12 inches in diameter and approximately 8 inches deep. With the shovel, carefully lift this top layer out of the hole, as if you are lifting a cake out of a tin. Set this patch of grass aside and continue digging to a depth of 18 inches. Fill the hole with water by using the hose or the large container.

3. Return to the hole between 24 and 48 hours later, to see how well the water has drained into the soil. When you return at the 48-hour point, if there is still water in the hole, there is a drainage situation. Because this location does not fully drain within 48 hours, the roots will be waterlogged, which will eventually kill the tree. If this is the situation, refill your hole. Replace the grass plug, being sure to water it well.

4. If the hole has passed the water drainage test, it is now time to test the pH of the soil, to see if the soil is acidic or alkaline. Place a small amount of the soil in the test tube provided in the pH testing kit. Add water and the required amount of the testing solution, according to the instructions. 

Cover the open mouth of the test tube and shake. Once mixed, use the provided color chart to check the color of the solution. Above 7.0 is alkaline and below 7.0 is acidic. The species of tree you are planting will determine the required pH level.

5. Depending on what the tree requires, before planting you can mix the required amount of sulfur into the soil to create more acidic results. To create more of an alkaline level, mix lime in.