What three numbers on the fertilizers mean?

The three numbers on a fertilizer package represent the percentage of nitrogen (N), phosphorus (P), and potassium (K) in the product. These numbers are always listed in the same order: N-P-K. For example, a fertilizer with a 10-20-10 analysis contains 10% nitrogen, 20% phosphorus, and 10% potassium.

Nitrogen is essential for plant growth and development. It is a component of proteins, nucleic acids, and chlorophyll. Phosphorus is also essential for plant growth. It is a component of cell walls, energy-rich molecules, and DNA. Potassium is important for water uptake, photosynthesis, and starch synthesis.

The ideal N-P-K ratio for a fertilizer depends on the type of plant being grown. For example, tomatoes need a high nitrogen fertilizer, while roses need a high phosphorus fertilizer. The soil test can also help determine the ideal N-P-K ratio for a particular garden.

It is important to use fertilizer according to the directions on the package. Over-fertilizing can damage plants and pollute the environment.