The Indogulf Bioag Organic Fertilizer Company are have best product which is a purely organic fertilizer useful for intensive organic cropping patterns. Kelp-based fertilizers contain potassium and a little nitrogen but the true benefits are the long-term effect they can have on your plants Fertilizers are materials that can be added to soil or plants, in order to provide nutrients and sustain growth. Typical organic fertilizers include all animal waste including meat processing waste, manure, slurry, and guano; plus plant based fertilizers such as compost; and biosolids.