In the April 2008 issue of North Carolina State University (NCSU) Cooperative Extension Service’s “Apple Production Newsletter,” NCSU soil fertility specialist Ron Gehl attributes the recent rise in fertilizer costs to a number of factors: increased demand, higher natural gas and transportation costs, and more reliance on imports. To help growers optimize fertilizer use without sacrificing yield, quality, or profitability, Gehl offers the following suggestions:
- Account for nutrients already in the soil. With rising fertilizer costs, it’s important to take advantage of the nutrients that are already in the soil. If you’re not already, perhaps now is a better time than ever to develop a soil sampling program for your farm. During the growing season, tissue sampling can also provide valuable information to monitor the nutrient status of the orchard. Unfortunately, many growers who routinely do soil or tissue samples often file the results away without fully understanding what information is provided.
- Apply only the nutrients needed. A somewhat common practice is to apply a multi-nutrient fertilizer product at a uniform rate throughout an orchard. But often times only one or two of the nutrients is actually needed. Does it make sense to apply a 19-19-19 product to a soil that has a very high soil phosphorus test? Sometimes applying extra nutrients can not only cost more money up front, but can result in other issues that affect return at harvest.
- Apply nutrients at appropriate times. Proper timing of lime and nutrient applications can affect overall efficiency of the nutrient program. There are several best management guidelines to follow regarding timing of nutrient applications.
- Calibrate your applicators. Calibrating fertilizer spreaders can sometimes be a tedious task, but calibration is important to ensure that the proper rates of fertilizer are being applied evenly. With high fertilizer prices, the time spent breaking in your application equipment can quickly pay off.
- Understand nutrient costs. Many products vary widely in cost, and one of the most important factors in optimizing return for your fertilizer inputs is knowing specifically how much each nutrient costs. When comparing potential sources of fertilizer, calculating and comparing the relative costs per pound of nutrient — not the costs per ton of fertilizer product — is crucial to making the most economical decisions for your farm.