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Ingredients in Fertilizers

Fertilizer is often an unspoken requirement when planting and growing. Fertilizer gives the plant a boost of nutrients and replenishes those that it lacks. Choosing the right fertilizer for a plant involves being aware of the fertilizer’s included nutrients and understanding its effects upon the plant. It is also important to understand the needs of the plant, as these needs vary.


Nitrogen is one of the three main ingredients, or macronutrients, in fertilizer. Nitrogen promotes the new growth of the green parts of flowers, such as grass and leaves. Nitrogen is an essential nutrient that plants use to complete the photosynthesis process. Hence, plants that lack the required nitrogen levels often show signs of yellowing. Though all plants require nitrogen, some plants require more nitrogen than others. Grass is one of the most common heavy feeders of high nitrogen levels.


Phosphorus is another main ingredient in fertilizer. This nutrient assists plants in developing strong root systems. A well developed root system improves the plant’s chance for a longer, healthier life span. Flowering plants with well developed root systems bloom larger, more colorful flowers. Therefore, fertilizers with higher levels of phosphorus are ideal for blooming plants.


Potassium is the third of the major ingredients, completing the N-P-K combination. This nutrient improves the overall health and development of the plant. Commonly referred to as Potash, potassium helps plants build stronger stems and bigger fruit. This nutrient basically assists the other nutrients in the soil and fertilizer in doing a better job for the plant.

Secondary Nutrients

Plants require more than just nitrogen, phosphorus and potassium to grow. There are a host of nutrients needed for good development. Secondary nutrients are required for optimum plant growth but in a reduced quantity. The secondary nutrients of fertilizers include calcium, magnesium and sulfur. Secondary nutrients help the plant to produce improved quantities, whether it is more fruit, more flowers or more foliage.


Fertilizer micronutrients are readily found in all soil types. Therefore, the need for these nutrients is much lower than the other ingredients. Still, micronutrient deficiencies can have an impact on the plant such as weakened conditions, weather susceptibility and reduced water efficiency. The micronutrients in fertilizer include boron, chlorine, cobalt, copper, iron, nickel and zinc.

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