Commercial Fertilizers Explained

Components

• Commercial fertilizers contain all essential nutrients for plant growth. The three most important, or primary, nutrients -- nitrogen, phosphorus and potassium -- are present in commercial fertilizers by weight and are indicated by the letters N-P-K on the bag. The amount is indicated by 10-10-10 or other numbers.

Nitrogen

• Nitrogen is the most essential nutrient for plant growth and is a critical part of living cells, proteins and enzymes. It is indicated by the letter N or the first number on commercial fertilizer bags. The nutrient supports metabolism and synthesis, aiding in the transfer of energy created by photosynthesis. Adequate nitrogen leads to rapid growth and healthy fruit and seed production. Nitrogen is especially important for forage crops.

Phosphorus

• The second important primary nutrient, phosphorus, is indicated by the letter P and second number on fertilizer bags. Phosphorus supports photosynthesis in plants and leads to formation of starch, sugars and oils in plants. The nutrient is important for the conversion of solar energy into chemical energy, leads to rapid growth, improves root health and increases plants' ability to tolerate stress.

Potassium

• Potassium is indicated by the letter K on commercial fertilizer bags and is the most absorbed nutrient after nitrogen and sometimes calcium. The nutrient helps to build proteins, supports photosynthesis in plants and improves quality of fruit. Potassium increases plant resistance to disease.