Fertilizer

Question

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?

Answer 1

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.