Plants require 16 elements for growth and these nutrients can be supplied from air, water, and fertilizers. The 16 elements are carbon (C), hydrogen (H), oxygen (O), phosphorus (P), potassium (K), nitrogen (N), sulfur (S), calcium (Ca), iron (Fe), magnesium (Mg), boron (B), manganese (Mn), copper (Cu), zinc (Zn), molybdenum (Mo), and chlorine (Cl). The key to successful management of a fertilizer program is to ensure adequate concentrations of all nutrients throughout the life cycle of the crop. Inadequate or excessive amounts of any nutrient result in poor crop performance. Excessive amounts can be especially troublesome since they can damage the crop, waste money and fertilizer resources, and pollute the environment when fertilizer is released during flushing of the nutrient delivery system.