Katherine Clarkson

Healthy ground is the foundation of a productive garden.

Some gardeners live in an area with dark mineral rich soil, but our western ground is equivalent to dirt. To have a prosperous garden you need to know what your soil comprises. The more you know, the easier it is to turn your poor land into a nutrient rich plant loving home. 

There are three major components that make up soil: sand, silt and clay. These components are necessary to determine the soil porosity, or the spaces where air and water live. To determine the different amounts, take a quart jar, add one-third of your garden soil and fill it with water until the jar is practically full. If you have a large garden, test the soil in several areas.

With the lid tightly secured, vigorously shake the jar until it breaks up all the large clumps. Next, set the jar on a window sill to observe how the particles separate.

The heaviest layer, which is made of gravel and coarse sand, will settle to the bottom first. Mark the top of this layer on the outside of the jar and let the jar sit undisturbed for three to four hours. This will allow the next layer, silt, to settle. Label the top of it on the outside of the jar. Subsequently, allow the jar to settle for 48 hours. The last layer, which is clay, will settle and label the top of it on the outside of the jar. 

With the three components labeled, use a ruler and measure the height of sand, silt and clay to identify what primary particles make up your soil. Above the clay will be a layer of mucky, cloudy water. This is organic matter. Organic matter in soil comes from plants and animals that are capable of or in the process of decay. For example, leaves and woody material that falls to the ground decomposes to nitrogen, phosphorous, potassium, calcium, magnesium and many other nutrients that living plants need to thrive.

Now that you understand your soil components, we will touch on ways to improve it.

In sandy soil, there are large air spaces that allow water to drain quickly, which will wash away nutrients that plants need to thrive. To improve sandy soil, add 3 to 4 inches of compost and mix it well. Mulch around your plants with wood chips, bark and straw to help keep moisture. Continue to add about 2 inches of organic matter each year.

If your soil is extremely dense, forms a crust when wet and is exceedingly compact, you have silt. Avoid working when it is wet to reduce the risk of compaction and add at least 1 inch of organic matter each year.

If you have a lot of clay, your soil will drain slowly and plant roots cannot push their way through it, causing them to be stunted. To improve, minimize tilling and mix 2 to 3 inches of organic matter to the surface of the soil. 

Every type of soil has unique physical characteristics and understanding each component will help you make the proper amendments to establish a thriving garden. Many other components need to be taken into consideration — such as its pH level, proper level of nutrients and the population of beneficial organisms — to have nutrient-rich soil.

To help answer your garden questions, or if you are interested in my landscaping services, please contact me at katherineclarkson2@gmail.com.

(Katherine Clarkson is the president of the Park County Master Gardeners. She lives in Wapiti.)