Soil test for sand, silt, and clay

[JaneK]

Success in the garden starts with the soil. Along with moisture and sunlight, the type of soil you are working with will determine whether plants thrive or die. Here's a quick way to test your soil. You'll need an empty straight-sided jar and a ruler. This should take an hour to set up and a full day to conclude.

To get your soil sample dig down to root level—about 15 centimetres —in the area that you want to test. Remove enough soil to fill the the jar to between one-third and one-half full. Next, fill the jar to the shoulder with water, then set the jar aside to let the soil soak up the water. Put the lid on the jar and shake it hard for about three minutes.

1. Set the jar down and look at your watch. In one minute, measure (with the ruler) the amount of sediment that has collected at the bottom. This is the sand in your soil.
2. Wait for another four minutes. Use the ruler to measure the sediment again. The difference between the two numbers will be the amount of silt in your soil. 
3. Take the third measurement in 24 hours. The difference between the second and third number will be the amount of clay in your soil. 

Calculate the percentages of sand, silt, and clay, which should add up to 100 percent. Healthy soil typically consists of 20 percent clay, 40 percent silt, and 40 percent sand. This simple test can help you to decide what to grow.

Jane