Healthy soil will have a few obvious hallmarks, including the presence of earthworms and the existence of healthy plant life in the desired planting area. Other techniques to determine more technical elements of a good planting area include digging a hole in the ground to determine water drainage capability and examining the soil's color and texture.
Some gardeners choose to send a soil sample off to a lab for thorough analysis. Soil quality can also be analyzed using advanced techniques such as the Willamette Valley Soil Quality Guide, a 10-step process developed by scientists at universities in Oregon. This test examines elements such as soil structure and compaction to determine overall soil quality.