Nitrogen is the "N" of NPK and applies to the first number listed on a fertilizer's label. Nitrogen gives plants a boost to produce leaves and new growth. On a cellular level, nitrogen provides much of plants' energy by being a component of proteins and chlorophyll. Yellow leaves and stunted growth are often signs of nitrogen deficiency in plants. Don't be tricked into thinking nitrogen is a cure-all for your plants; too much nitrogen results in plants with lush foliage but no flowers or fruit, and it increases the risk of insect infestation on the plants.
The "P" in NPK on a fertilizer bag stands for phosphorus. It corresponds to the second number on the fertilizer's label. Phosphorus is essential for many aspects of healthy, attractive plants, including flower formation, root development and fruit production. Plants with a phosphorus deficiency often have underdeveloped leaves with purple or bluish-green splotches. The plants also fail to flower or set fruit, which also may happen when too much nitrogen present in soil. Avoid the temptation to overdose your plants with phosphorus in the hope of getting more blooms. Phosphorus deficiency is rare, and too much of the nutrient can prevent the plants from absorbing other nutrients.
The third number on a plant fertilizer's label is potassium, symbolized by the letter "K." Unlike the lush leaves from nitrogen and bright flowers from phosphorus, potassium has a more subtle role. It aids in building proteins and starches that strengthen plants. Potassium also gets plants through stressful times, such as heat, drought and disease. Yellow leaf tips or leaves that look scorched indicate a potassium deficiency. Although potassium builds strong plants, too much potassium blocks the absorption of other nutrients, which weakens plants.
Company name:Wenzhou XIFA Industrial Co.,Ltd
Company ADD:Lingxi Industrial park,Cangnan Country,Wenzhou city,Zhejiang, China