We now know that the 3 numbers on fertilizer bags are percentages. A fertilizer that contains only one macro-nutrient will have “0” in the other values. The first number is the amount of nitrogen (N), the second number is the amount of phosphate (P 2 O 5) and the third number is the amount of potash (K 2 O).
For example: a bag of fertilizer labelled “15-10-5” would contain 15% nitrogen (N) by weight, 10% phosphorus (P) by weight, and 5% potassium (K) by weight. It doesn’t matter if it is liquid or dry fertilizer, as the numbers represent the percent by weight of …

The manufacturers assume the user knows, but 80% of people do not. Fertilizer numbers aside, the first choice you need to make when looking at fertilizers for your vegetable gardens is whether you’re going to use an organic fertilizer or a chemical (synthesized or manufactured) fertilizer. Accepted Truth Vs Common Philosophy . A 1-2-1 fertilizer could be labeled 5-10-5, 10-20-10, or any number … So now that you know what the fertilizer numbers or NPK values stand for, you need to know WHY there's so important.

A fertilizer ratio of 10-5-5 requires twice as much fertilizer to achieve the same concentration as one with a ratio of 20-10-10.

Fertilizers that have equal numbers can generally be used as an all-purpose fertilizer.

The higher the number, the more nitrogen the fertilizer provides. It may seem intimidating, but you can figure it out. Other Plant Nutrients.

Phosphorus (P) promotes root development, which helps to anchor and strengthen plants.


We now know that the 3 numbers on fertilizer bags are percentages. These three numbers represent nitrogen, phosphorous, and potassium respectively (N-P-K). What the Fertilizer Numbers Mean.

Some fertilizers have more than three numbers, and in those cases the extra numbers represent other nutrients. This becomes important when you are looking for fertilizer to meet a specific need. The numbers on the front of your lawn fertilizer bag are a “fertilizer grade”, sometimes called an “N-P-K ratio”, which describes how much Nitrogen, Phosphorus, and Potassium it contains.

Various grades are available because differing types of plants thrive better with a different balance of nutrients. This post does apply to North America and most of Europe. These three numbers represent the primary nutrients (nitrogen(N) - phosphorus(P) - potassium(K)). What Fertilizer Numbers Mean: There are three numbers in the form of N-P-K on a fertilizer bag which represent the main elements found in the fertilizer. It also increases bloom and fruit production. Tomatoes and root crops favor “snacks” of 5-10-10.

For example, if the numbers on the fertilizer are 10-10-10, you can divide 100 by 10, and this will let you know that you need 10 pounds of the fertilizer to add 1 pound of the nutrient to the soil. If you had only one product to work with, 10-10-10 would be my recommendation. In other words, you would set your spreader to apply the 20-10-10 at half the application rate that you would use for the 10-5-5. It doesn’t matter if it is liquid or dry fertilizer, as the numbers represent the percent by … Most bags do not tell you what the numbers stand for in terms of nutrients.

This is the percentage by weight of the N, P, and K found in the fertilizer.

You should know the difference between each of these before choosing which one to …

Fertilizer Labels: What N-P-K Numbers Mean Beautiful lawns and gardens start with healthy, well-nourished plants. When it comes to fertilizers, much attention is paid to nitrogen, phosphorus, and potassium, but there are other key nutrients needed for overall plant health as well, though in smaller quantities.