Light-colored subsoil layers deeper in the ground indicate that lower soil levels have been altered by limestone, which suggests your yard may not have good drainage.
When soil loses its reddish tint and starts taking on gray and green tones, it's a strong indicator that harmful anaerobic bacteria are removing oxygen from the soil.
Yellow soil on the paler side indicates that it’s leached of nutrients. However, if the yellow is a rich shade, it means there are high amounts of iron oxide in the soil.
Although yellow soil isn't ideal, it may work for raising hardier plant varieties. Mangoes, oranges, and potatoes are common fruits and vegetables grown under these conditions.
Reddish-colored earth has lots of iron oxide and clay, making it good for fruits and vegetables. If it’s bright red, it's draining well and great for acidic-favoring plants.
However, if the red color appears washed out, there are few nutrients present. Very dark red soil may be oversaturated, which can lead to dangerous bacterial growth.
Middle-toned brown dirt contains moderate amounts of nutrients, minerals, and moisture. Although it isn't as ideal as deeper brown soil, it has the potential to sustain life.