Understanding the Difference Between Dirt and Soil Most people use the terms "dirt" and "soil" interchangeably. I did too, before I started growing seriously. But they are not the same thing. Soil is alive. It's a full ecosystem—microorganisms, fungi, worms, decomposed organic matter—all working together to create an environment where growth is possible. It holds water without drowning roots. It drains without drying out. It feeds slowly and consistently. A soil test is alway