Question

Critical limit of plant nutrient element and hunger signs

Answer 1

These are nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. The trace elements are measured on a part per million dry weight basis. For example, a typical analysis of a dried leaf from a healthy cherimoya might show 2% nitrogen, 1% potassium, 100 ppm (parts per million) iron and 50 ppm boron.