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An explanation of the purpose for each component of chemical fertilizers

"The reason I'm surfing is to find what nutrients are referred to in fertilizers, i.e. 10-20-10, and which nutrient aids growth of roots, stem and leaves in plants."

Always choose an appropriate fertilizer

Fertilizer analysis

Understanding the fertilizer analysis is essential when choosing the right fertilizer to purchase and apply. Fertilizers, such as 10-20-10, are identified on their package by their chemical analysis. The three numbers on the bag or container refer to the percentages of nitrogen, phosphorus, and potassium components in the fertilizer.

Chemical fertilizers for the home garden are available in two forms. The granular form is sprinkled on the soil and worked in with a tiller or hand tool. Water soluble types are mixed with water and the feeding is accomplished by sprinkling onto the leaves of the plant (foliar feeding) or used as part of the watering process, in which the plant takes in the nutrients systemically (through the roots).

Fertilizer components and what each does for your plants

  • The first number in a fertilizer formula is the nitrogen content..... Nitrogen is used by plants for producing leaf growth and greener, lusher leaves.
  • The second number in a fertilizer formula is the phosphorus content..... Phosphorus is used by plant to increase fruit development and to produce a strong root system.
  • The third number in a fertilizer formula is the potassium (potash) content..... Potassium is used by plants for flower color and size. It is also important to the strength of the plant.

Using Fertilizers Properly

The easiest way to explain this would be that a 100# bag of 10-20-10 converted to component weight would equal 25# of nitrogen, 50# of phosphate, and 25# of potash. Before applying fertilizer to the garden, it is best to test your soil (or have it tested by sending a sample to your local county ag agent.)

The 'basics' testing can be done with the use of reasonably inexpensive home testing kits that can be purchased at most garden stores. These soil tests will tell you the level of nutrients that are already in the soil, as well as the acidity (pH) of the soil.

Adjusting the pH of your soil is essential, because some nutrients may become unavailable to your plants if the soil pH is above or below a certain range.

If your test is done by your county extension service, the test results will be much more detailed, and will also provide their recommendations for any needed additions of lime and fertilizer to your soil. The timing of the application of fertilizers is very important. Too much fertilizer, or applying it at the wrong time can lead to an over abundance of foliage, delayed flowering, leaf and root burn, or even plant death due to excess fertilizer!

It is essential that you always read and follow the product recommendations for fertilizers, or any other garden chemicals.

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