What it tests
Particle Size: Soil particles size varies greatly because each particle could be sand, silt, or clay and each of the ranges in different diameters. The size of soil particles is important. The amount of open space between the particles influences how easily water moves through soil and how much water the soil will hold. Soil can have an unbalanced portion of each type of particle which would affect the soils ability to be optimal for your gardening solution. Certain plants thrive in specific unbalances as well.