x
 
 
Learn which plants thrive in your Hardiness Zone with our new interactive map!

How to Test Soil Moisture

By S.F. Heron ; Updated September 21, 2017

The ability of soil to hold moisture dictates the condition of your lawn and garden. Thick clay soil absorbs small amounts of water, causing runoff and erosion of topsoil. Healthy soil can hold water like a sponge, allowing a gradual release of moisture into the surrounding area. Learning how to test soil moisture doesn't need to involve complex tools. Basic knowledge and experience will help you accurately gauge the moisture level of your soil so that you can water your landscape as needed.

Choose various locations in your garden or lawn to take soil samples. Press the trowel straight down into the soil to create an elongated hole about 6 inches deep. Scoop out the soil for examination.

Read the cues during the sample digging. If pushing the trowel into the soil requires great force, the soil probably needs watering.

Examine the sample. Healthy soil will retain moisture down at least 6 to 8 inches. During times of drought or little rain, the top layers will dry quickly. Extended periods of drought will progress through the layers of soil to reach the deepest layers.

Grasp a section of soil from the top of the sample in the palm of your hand. Squeeze your hand together to form a ball of dirt. If the ball crumbles and doesn't hold shape, the soil is extremely dry regardless of composition. Soil that can be squeezed into a ball that holds the rounded shape contains adequate water. No droplets of water should appear when squeezing the ball of dirt.

Perform the same test on a lower portion of your soil sample. Upper- and lower-level soil samples may have distinctly different moisture levels.

Evaluate the soil moisture levels. Most soil ranges somewhere between the crumbly ball of dirt and the well-rounded sample of moist earth. Powdery, dry soil requires a slow, deep watering to restore soil moisture levels.

Continue evaluating the remaining soil samples from your garden and lawn to provide a clear picture of the moisture levels in your landscape. Create a plan to adequately water your property so that future soil samples result in a rounded ball of dirt that retains its shape after it has been released.

 

Things You Will Need

  • Trowel

Tips

  • Soil moisture gauges and meters offer some assistance in testing soil moisture. The results of these gauges need to monitored and charted to get an accurate picture of the soil moisture content. Digging up samples of the soil and gauging moisture levels by touch presents an affordable way to evaluate soil moisture.
  • Watering deeply involves the gradual application over time of moisture to your lawn and garden. In many cases, bad soil conditioning complicates this task. Adding amendments such as peat moss, compost or other organic additives can improve the moisture retention capabilities of your soil.

References