• PLANT MINERAL NUTRITION
  • I. Criteria of essentiality (DI Arnon & PR Stout, 1939)
  • II. Essential elements for normal plant growth:

  • C HOPKNS CaFe Mg Na Cl .
  •                                 (Mighty good) (Not always) (Clean)
  • CuMn CoZn MoB(y)!
  • III.  Commercial Fertilizers sold as %N, %P, %K