Meaning of Numbers on Fertilizer Bags
Many people may wonder what do the numbers on fertilizer bags mean. Actually, it is regulated by law and fertilizer industry that these numbers must be present on each bag of the fertilizer product. When you applying fertilizers on you trees or shrubs in your garden, you might have different soil conditions in which the percentage of nutrition required by your plants might be different. So, you can go to the fertilizer store to buy the correct type to balance the nutrition for your soil.
The numbers on the fertilizer bags are actually represent the percentage of three most important elements for plants, namely, nitrogen, phosphorus and potassium. For example, a fertilizer bag marked as 25-15-10 means the percentage of them is 25%(nitrogen), 15%(phosphorus) and 10%(potassium). Since the sum of these percentages is less than 100%, there are other micro elements which take the remaining 50%. These micro-nutrients might be different for each brand of fertilizer. Also, each type of fertilizer normally contains some filler materials which are responsible for evening applying the nutrients within one place. This type of material plays a very important role for the health of your trees. Without it you may over-apply or under-apply fertilizers in one area which will weaken the health of the plants.
So, understanding the numbers on the fertilizer bags is a very important step before the purchase. You should do some rough calculations on the nutrition requirement prior to buying anything. Nitrogen is the building blocks of plant cells. It can make foliage green and make stem grow quickly. Phosphorus is essential in the root system which will help the plants to absorb nutrition and water from soil. Potassium helps the plants to strengthen the foliage and stem, and improve the plants’ immune system.
In a word, the numbers on the bags represent the percentage of three most important nutrition elements required for the growth of trees. You can easily compare one with another to choose the best type for your backyard.
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