Worm castings and the microbiological life they contain are a superior soil amendment that enables everyone to grow great crops and plants organically and easily. The wide diversity and large numbers of microbes break down organic materials in soil to provide a wide variety of nutrients to plants.
These microbes are also used to brew aerobic teas that are used to innoculate your soil to "jump start" the soil's life.
By using the tea as a foliar spray, the microbes act as a disease supressant by competing with harmful microbes such as fungi and creating a protective barrier to leaf cells.