Well, I grow organically and I have been posting my grow logs here for years. Like the ad for Prego tomato sauce, "it's in there". The microbes are from the organic composts, it is called Bio-Tone in the Espoma line of organic nutrients, Plant Success I use contains mycorrhizae. Brewing earth worm casting tea or compost tea I am feeding microorganisms in the EWC or compost to give them a good start before I introduce them to the plants. You won't see me using the same terms (EM or AEM). But, "it's in there".