Deciding what to apply

Crops need nutrients in the right amounts and at the right times. For field crops, soils are a source of these nutrients, as are manures, fertilizers and other soil amendments.

Deciding what to apply – the amounts and types of soil amendments – depends on cost, availability, the nutrient values of the amendment, and crop requirements among other factors.

What’s new

A gypsum factsheet (PDF, 60.3 KB) explaining the value of gypsum as a soil amendment for managing soil health and fertility.

• Gypsum is a soil amendment that provides plant-available calcium and sulphur
• Gypsum helps to improve soil structure and water movement including improving water infiltration and lowering runoff and erosion risk
• Gypsum can be used to manage sodic soil
• Gypsum is not a liming product

Soil nutrient testing

A major reason for soil testing is to evaluate soil fertility, the ability of the soil to supply crops with nutrients:

• Soil Nutrient Testing

Manure application

Animal manures can be a beneficial resource of nutrients and organic matter for soil and crops or, they can be a waste depending on how they are managed.  Read more:

• Manure Application

Nutrient ratios

Healthy crops can grow under a wide range of nutrient balances when nutrients are sufficient and pH is suitable. Ratios can help describe a soil, but they should not be the main basis for fertilizer decisions.

• Nutrient ratios factsheet (PDF, 474 KB)

Phosphorus management

There are unique challenges with phosphorus, an essential plant nutrient in limited supply. Globally, phosphorous excesses accumulate in some agricultural regions and depletions occur in others. Learn more about why this matters and strategies to better use phosphorus resources:

• Phosphorus Management

Micronutrients for field crops

Micronutrients are required by plants in small amounts relative to macronutrients such as nitrogen, phosphorus, and potassium. However, they are nonetheless essential to plants:

• Micronutrients for Field Crops

Fertilizer trials

There is almost always room to improve something about nutrient applications. In demonstration trials, different nutrient application practices are compared on small parts of farms. Results can then be used to improve crop yield or quality, reduce fertilizer costs, or minimize environmental risks from nutrient losses.  Learn more:

• Fertilizer trials

Gypsum as a soil amendment

Gypsum is a soil amendment that supplies calcium and sulphur. It can improve soil structure, reduce surface crusting, increase water infiltration and retention, and reduce runoff and erosion. It can also be used to reduce salinity in sodic soils. Gypsum is not a liming material and should not be used as a substitute for agricultural lime where soil acidity needs to be corrected.

• Learn more about gypsum (PDF, 285 KB)