What is the key aspect of making informed decisions about fertilizer use?

Using soil testing data is essential for making informed decisions about fertilizer use because it provides objective, quantifiable insights into the nutrient availability and needs of the soil. By analyzing soil samples, farmers can determine the specific nutrient deficiencies or excesses present, allowing them to tailor their fertilizer application to match the actual requirements of their crops. This ensures that the plants receive the necessary nutrients without the risk of over-fertilization, which can lead to environmental concerns such as runoff and water pollution.

Relying solely on visual inspection of crops may lead to subjective interpretations that can miss underlying nutrient issues that are not immediately visible. Weather forecasts are important for planning applications and timing but do not offer the detailed information needed to determine specific fertilizer needs. Likewise, relying on farmer intuition can be helpful but lacks the empirical support that soil testing provides, which can lead to more reliable and effective fertilizer management strategies.