what does npk fertilizer mean?
Plant food or fertiliser (fertilizer in the U.S.) provide the nutrients for healthy plant growth. ... 'NPK' stand for Nitrogen, Phosphorous, K for Potassium or Potash. '5 – 3 – 5' are the ratios of NP&K in the pack or bottle. In this case 5 parts Nitrogen, 3 parts Phosphorous, 5 parts Potash.