Microbial is used to stimulate a plant's inbuilt immune system, thus improving overall plant health and increased resistance to attacks from pests and diseases.

With conventional horticultural practices i.e soil, most bacteria are beneficial to plants in terms of breaking down organic matter enabling the mineral elements contained within to be readily absorbed by the plant. In a hydroponic or aeroponic environment, these beneficials are not present, therefore the potential for problem airborne or soil borne micro-organisms attacking hydroponic crops is very high.