I genuinely don’t think there is a subject more overwhelming or misunderstood than fertilizers. What are the three numbers? Is Nitrogen more important than Phosphorous? Do I need to get a vegetable fertilizer? Is Bone Meal a fertilizer? Do I fertilize new sod? What about my houseplants like orchids? All valid questions and we hear them rather often.
Essentially every fertilizer will have three (3) numbers on the package. The numbers are, in order, nitrogen (N), phosphorous (P), potassium (K). These are the macro-nutrients used by plants. The fertilizer you need will be represented by these numbers.
Nitrogen is primarily above ground leafy growth. Phosphorous is development of roots, flowers and fruits. Potassium is keeping the plant healthy and all functions operating normally. Lawn will have a much higher nitrogen count. Veggies will have a higher phosphorous, or maybe potassium count. A good rule of thumb is all plants benefit from fertilizer, and more is not better.