Have disagreement with my friend and maybe you can help me. He claims to have some 100 100 100 fertilizer, I haven\'t seen it. Claims to have used it all. There\'s no such thing is there?
The NPK numbers refer to what percent of each measure of fertilizer is Nitrogen, Phosphorus and Potassium. The percents do not add up to 100% because fertilizers are mostly inactive ingredients to carry the NPK plus trace elements. It is mathematically impossible for NPK to add up to 300%. Perhaps your friend is confusing 10-10-10 or is thinking that his fertilizer provides 100% of what his plants need. There is no RDA, recommended daily allowance, for plants but he is thinking along similar lines, perhaps.