Salvia Small Talk: How to Determine Soil Moisture Level
This is the second article in a three-part series on efficient watering.
Basic tools for estimating soil moisture include your hands and simple tools, such as a trowel, screwdriver and long metal rod. The first method, which uses the metal tools, might be called the 'poke technique.'
If you are testing the depth to which water has penetrated around a new planting and only need to check to a depth of about 6 inches, the trowel will be sufficient. For a few more inches, you need the screwdriver. At a distance just outside the canopy of the plant, poke the trowel or screwdriver straight down into the soil. If they sink in to their hilts and come out moist but not muddy, then the watering is sufficient.
Although the trowel and screwdriver may be sufficient for checking the shallow root growth of sages grown as annual bedding plants -- such as Scarlet Sage (Salvia splendens spp.) -- you'll need the rod for perennial plantings. Use a thin one that is 24 to 36 inches long for testing the soil near established plantings. By marking the rod at 6-inch increments, you can easily measure the depth to which it sinks before meeting resistance.
A second way to test for moisture is the 'feel method' of squeezing a lump of soil in your hands to get a feel for its moisture. Dig down 4 to 8 inches or further to gain the handful of soil. For sandy or loamy soil, sufficient moisture is demonstrated when some of the soil sticks on your hands and leaves a stain.
Moist clay soil should also leave a stain. Yet if it won't break apart, that means it is too dry. Conversely, if water runs off of either kind of soil when you squeeze it, then you are overwatering. If you need more tips for avoiding either under-watering or overwatering, please contact us. Next up in this series: What Is an Inch of Water?