Dr. Earth 1.5 lb. 7-3-1 Bat Guano Organic Fertilizer. An excellent source of fast-acting nitrogen, it contains Dr. Earth Trubiotic, a broad-spectrum biological soil inoculant that promotes the growth of all types of plants. This fertilizer can be used as a fertilizer tea for all applications. It is 100% organic and natural, and it is safe for people and pets.