A vaccine for stimulating root growth and boosting plant resistance via seed treatment and spraying at the beginning of the growing season. It contains a special blend of Effective Microorganisms promoting healthy plant growth already from the germination stage, and improving their condition during growth. Depending on the method of administration, EM Multi Grower: accelerates growth of the root system, strengthens and levels up germinating seeds, increases yield potential, stimulates regeneration of plant tissues after damage caused by stressful conditions, improves plant health and prevents growth of pathogenic microflora.