Fertilizer is a mixture because the atoms that make up the substance are not present in a set ratio.
Fertilizers primarily contain nitrogen, phosphorus and potassium in various amounts. They often also contain calcium, magnesium, boron, iron, copper and other minerals.
This ratio is listed on the packaging of fertilizer as the NPK ratio.
Compound, Element and Mixtures
Elements are things that are purely one substance. Carbon is an element and so is oxygen.
Compounds are substances that have more than one element present in a fixed ratio. Water is a compound, it is made up of hydrogen and oxygen in a fixed ratio, for each hydrogen molecule there are always 2 oxygen molecules.
Mixtures on the other hand contain more than one element, but the ratio can change from substance to substance. Soil is a mixture as it can have many different compositions.
Tea is another mixture as it can be strong or weak, it can contain lots of tea molecules or very few.
Because fertilizers are made by combining many elements in various ratios. The NPK ratio is what gardeners and farmers consider when choosing a fertilizer, so there are many NPK ratios available on the market.
There are even companies that create custom NPK fertilizers for specific applications in commercial farming.
What Elements are In Fertilizer?
Fertilizer is made up of three main elements:
These three elements are the most important nutrients for healthy plant growth. Soil tests often test for nitrogen, phosphorus, and potassium levels in soil and make recommendations for fertilizer application.
These elements leave the soil at various rates so it is important to apply fertilizers only when a soil test indicates that a nutrient is lacking.
Over application of phosphorus and potassium can be detrimental to plant growth as it is immoble in the soil and can impede a plant’s ability to absorb and utilize nitrogen.
They also often contain:
Often referred to as trace minerals, these elements support healthy plants and soil, but are not as necessary as nitrogen, phosphorus and potassium.
These elements are essential for high yields and healthy crops. Some of these nutrients are important for preventing plant disease.
Tomatoes, for example, can suffer from end rot if they are not provided with enough calcium. This can result in lower yields, mushy spots on fruit and malformed fruit.
Gardeners who maintain green lawns often apply nitrogen regularly to keep the grass green longer.
A high quality soil test will give levels for these minerals and make recommendations for correcting deficiencies.
Organic fertilizers like compound, bone and blood meal, manure and feather meal are all examples of organic fertilizers that can add minerals to the soil and improve soil health over time.
What Is Fertilizer?
Fertilizers are typically made up of various ratios of nitrogen, phosphorus and potassium. These elements exist in fertilizer in various ratios.
Fertilizers will list the NPK ratio on the outside of the bag and these are formulated to support the growth of various crops.
For example, lettuce requires a lot of nitrogen to thrive and corn requires a very balanced NPK fertilizer to produce healthy yields. Gardeners who are cultivating these plants will choose an appropriate NPK fertilizer to apply to these crops.
Organic fertilizers like poultry manure, blood meal, and compost also have NPK ratios, but they contain many many other elements.
Some fertilizers will list other elements contained in the products on the packaging.
Fertilizers will commonly list their contents of: magnesium, calcium, sulfur and iron.
These compounds may affect the ph of the soil, so it is important to monitor.
Are Fertilizers Mixtures?
Fertilizers contain many elements in various ratios, this makes fertilizer a mixture.
Mixtures are substances that contain multiple molecules without a fixed ratio. Coffee is a common example of a mixture. It contains coffee and water, but the amount of each can vary from pot to pot (strong or weak coffee).
Commercially produced fertilizers are produced with a variety of ratios by design. Different ratios are preferred for different crops and to address soil deficiencies.
Gardeners who maintain those lush greens at the golf club use a high nitrogen fertilizer (maybe even pure nitrogen) to the grass to keep it growing green longer into the winter.
Is Fertilizer a Compound?
Individual types of fertilizers can be classified as compounds because they are manufactured in a set ratio of nitrogen, phosphorus and potassium.
While the whole category of fertilizer is better classified as a mixture, individual fertilizers could be classified as a compound.
Compound fertilizers is a term used to describe manufactured fertilizers that contain 2 or more nutrients.
Masterblend is a commonly used compound fertilizer.
Compound fertilizer can also be created by combining granular single nutrient fertilizers. This is a common practice on larger farms.
Is Fertilizer an Element?
Fertilizer contains many different elements and it is not one element. The most plentiful elements in commercial fertilizer are nitrogen, phosphorus and potassium. In commercial production of fertilizer the pure elements may be combined to create fertilizer.
Fertilizers that are manufactured in this way can be classified as a compound as they are created in fixed ratios.
Fertilizer as it is used in general conversation is not an element, but a mixture.
What Is Fertilizer?
Fertilizer is a term that is used broadly to refer to any substance that is added to plants as a liquid or solid to increase yields, quality or aesthetic qualities of crops.
Many fertilizers that are used in large commercial farming operations are primarily composed of nitrogen, phosphorus and potassium.
These fertilizers are then applied in specific ratios and at specific times of year to produce a higher yield of crops or extend a growing season.
Fertilizer can also refer to organic materials that are used for the same purpose.
Fertilizer is classified as a mixture because it is a combination of many elements without a fixed ratio. There is no set NPK ratio for every fertilizer, this ratio varies from product to product which is what lands fertilizer in the category of mixture.