If you're a gardener or farmer, you've probably heard of NPK, or nitrogen, phosphorus, and potassium. These three nutrients are essential for plant growth, and understanding their role in your soil can help you grow healthy, productive plants. Nitrogen (N) is a critical component of plant growth, and it's responsible for helping plants produce leaves, stems, and other vegetative growth. Plants that lack nitrogen often have yellowing leaves and stunted growth, while those with too much nitrogen may produce too many leaves at the expense of flowers or fruit. Good sources of nitrogen include manure, compost, blood meal, and fish meal. Phosphorus (P) is essential for root growth, seed formation, and overall plant health. Plants that lack phosphorus may have poor root development and difficulty setting fruit or seeds, while those with too much phosphorus may have stunted growth and difficulty absorbing other nutrients. Good sources of phosphorus include bone meal, rock phosphat...