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.

Soil nutrient testing

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

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:

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:

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:

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: