Fertilizers Used in Agriculture

Fertilizer is another word for plant food. In other words, fertilizer is a substance that adds nutrients to soil and enhances plant growth. According to the U.S. Environmental Protection Agency, agricultural fertilizers always contain three essential nutrients: nitrogen, phosphorus and potassium. These fertilizers can come from organic sources, like manure, or commercial products.

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Fertilizers Used in Agriculture

Organic Fertilizers

Organic fertilizers are derived from plant or animal waste and naturally contain important plant nutrients. Common organic fertilizers, like compost or cow manure, are worked into the soil during crop planting.

Organic fertilizers are sometimes referred to as bulky fertilizers because they take up a significant amount of space, making them difficult to transport. For this reason, most organic fertilizers are usually only used where they were produced.

Treated sewage sludge, known as biosolid, is another effective organic fertilizer. Biosolids are rich in nutrients that, when treated and processed, stimulate plant growth and maintain healthy soil. As the E.P.A. points out, this recycling of biosolids into fertilizer can improve water quality, reduce pollution and contribute to sustainable agriculture.

Inorganic Fertilizers

Inorganic fertilizers are synthesized by a manufacturer to include important plant nutrients in a compact manner for easy transport. These synthetic substances are designed to create specific results by using varying chemical ingredients. They can even be tailored to specific crops or growing regions by adding specific nutrients, like adding a high concentration of energy-boosting phosphorus to a soybean fertilizer.

To determine the nutrients needed from a fertilizer, farmers should have their soil tested. Then, they can determine the best balance of nutrients for their crops. You can contact your local Department of Agriculture to find a company to test your soil.

Other inorganic fertilizers have additives to improve soil condition or to repel insects from crops. The International Fertilizer Industry Association produces a best-practices guide to assist farmers and the agricultural industry in choosing and using fertilizers in the best way.

Comparing Fertilizer Choices

When it comes to thriving crops, fertilizer is almost always necessary. Farmers and gardeners must choose to take the organic route or to go with commercial products, which isn't an easy decision. Both inorganic and organic fertilizers have pros and cons.

Organic fertilizers are natural and an ideal choice for eco-friendly agriculturalists. In contrast to synthetic inorganic fertilizers, they pose no threat to water quality and are generally nontoxic to plants and animals. Instead of fossil fuels, organic fertilizers are made from renewable sources and are a very sustainable option.

Organic fertilizers rely on soil organisms to break down organic matter, so nutrients are released relatively slowly. This can be a disadvantage, as inorganic fertilizers are often ready to release nutrient immediately upon application.

Inorganic fertilizers can leach into soil and wash away with rain, contaminating the environment with toxic chemicals. This can negatively impact both human and environmental health.

However, inorganic fertilizers tend to get the job done quickly and reliably. The choice between organic and inorganic fertilizers is in the hands of the individual and depends on preference, priorities and yield needs.