Why Farmers Use Fertilizer

Every harvested crop removes nutrients from a field. Farmers use fertilizer, manure, legumes and other nutrient sources to replace or supplement what crops need. The important question is not simply whether fertilizer is used, but which nutrients are needed, how much is applied and how losses are managed.

Plants need nutrients

Nitrogen, phosphorus, potassium, sulphur and other nutrients support plant growth. Soil can supply some of them, but availability differs among fields and changes over time.

Harvest exports nutrients

Grain, vegetables, hay and other harvested material physically remove nutrients from the farm field. Maintaining productive soil often requires nutrient replacement.

Fertilizer can come from different sources

Commercial fertilizers provide concentrated nutrients. Manure and compost can recycle nutrients and organic matter. Legumes can contribute biologically fixed nitrogen. Farms often use combinations.

Soil testing improves decisions

Alberta recommends using soil tests along with crop needs, field conditions and experience to develop fertilizer programs.

More is not automatically better

Nutrients that crops do not use can be lost to air or water or accumulate in soil. Good management attempts to match nutrient source, rate, timing and placement to crop requirements.

Fertilizer is regulated

CFIA regulates fertilizers and supplements sold or imported in Canada under the Fertilizers Act and Regulations, including safety and labelling requirements.

Soil tests do not prescribe one automatic fertilizer rate

A laboratory result is one piece of a nutrient-management decision. Farmers also consider expected crop yield, previous crops, manure history, soil moisture, nutrient placement and economic conditions. Recommendations can change as those assumptions change.

This is why two neighbouring fields can reasonably receive different fertilizer programs.

The 4R idea provides a useful framework

Nutrient stewardship is often described around applying the right nutrient source at the right rate, right time and right place. The principle is straightforward: give crops access to needed nutrients while reducing avoidable losses.

Actual implementation varies by crop, soil and farm equipment. Fertilizer may be placed with or near seed, banded separately or applied at other times depending on the nutrient and system.

Nutrients can move beyond the crop

Nitrogen can be lost through several pathways, while phosphorus movement can contribute to water-quality problems. These losses cost farmers money as well as creating environmental concerns. Better nutrient-use efficiency can therefore serve both economic and environmental goals.

The useful consumer question is not simply “Do you use fertilizer?” It is “How do you decide what the crop needs and how do you manage nutrient losses?”

Putting it into practice

Agriculture rarely fits into simple labels. Two farms growing the same crop can make different decisions because their soil, weather, equipment, markets and economics are different. A practice that solves one problem can create a tradeoff somewhere else.

For consumers, the most useful approach is to move from broad labels to specific questions. Ask what was done, why it was done, what standards apply and how the producer evaluates the result. For farmers, explaining those decisions clearly can build more trust than relying on marketing language.

The PureFarmFresh approach

PureFarmFresh supports Alberta agriculture while leaving room for honest discussion about how food is produced. Conventional, organic, regenerative, small and large farms can all involve thoughtful people making complex decisions.

Know where it comes from. Understand how it was produced. Ask better questions.

We explain the practice. You decide what matters to you.

Sources & Further Reading

Reviewed: September 2026

Agricultural regulations, programs and production guidance can change. Use the linked Government of Alberta, Government of Canada and CFIA resources for current requirements. This article is general educational information.