To understand how to best nourish their crops in an economical manner, farmers study soil types, soil pH, soil tilth (physical structure), nutrient levels, rainfall patterns, drainage and a host of other specific variables associated with a specific crop; whether fruit, vegetables, cotton, corn, wheat or soybeans.
The overarching intent of any nutrient management effort is to get the right source of fertilizer at the right rate at the right time in the right place to optimize the genetic expression of the crop in the field. Fertilizer nourishes plants, eliminates stress due to nutrient deficiency and helps the crop better withstand other stresses.
So, how do farmers know what the right sources, right rates, times and places are? Analyzing the soil before planting the crop is one way to answer these questions, a process commonly known as a soil test. Another is to analyze the plants themselves as they grow or take a tissue sample.
This information helps guide the farmer in making fertilizer decisions before the growing season begins. The farmer can use fertilizer prices, the expected price at harvest of the crop(s) he or she plans to plant, and anticipated yields to determine the fertilizer program that will be most effective and profitable.