One of the first steps toward nutrient use efficiency and optimizing crop yields is soil testing. After all, it’s impossible to improve the efficiency of your nutrients if you don’t even know what nutrients you’re working with to start.
Soil testing is a must-do to optimize and maintain soil health while improving nutrient efficiency. Understanding when and why to conduct soil tests, as well as what to do with the results, can help make the most of the nutrients that exist in or are added to the soil.
When To Soil Test
The right time to take soil samples is in rhythm with the crop rotation. The University of Illinois Extension recommends soil testing in the fall, every three to five years.
Samples are taken in the fall to allow ample time for planning a crop nutrition program based on the 4Rs of Nutrient Stewardship: applying the right nutrient source at the right rate, time and place.
Why Soil Test
Soil testing provides valuable information about nutrient content and overall soil health. Knowing the levels of essential macro and micronutrients allows growers to tailor fertilizer applications, which can lead to more efficient use of inputs and increased Return on Fertilizer Investment (ROFI).
It may seem like one more thing to do during the busy season, but soil testing helps growers identify how to maximize their nutrient use efficiency by ensuring the soil nutrient profile is in the right balance to amplify the natural relationship nutrients have with each other.
Some nutrients can antagonize others, making them unavailable to growing crops. The key to maximizing the nutrients in the soil is to ensure each nutrient is in balance with the other nutrients. When that balance is achieved, nutrients have a natural synergy with each other that helps them become more available and accessible to crops.
When recent test results are combined with previous on-farm and local data, soil testing serves as the best guide available for determining nutrient needs for growing crops. It helps develop a Balanced Crop Nutrition program and maximize nutrient use efficiency for profitable, efficient and environmentally responsible farming operations.
What To Do With Soil Test Results
Once soil test results are in, the next steps are crucial for effective implementation:
- Analyze the Results: Make time to sit down and review results to understand the soil’s nutrient levels, pH and organic matter percentages.
- Evaluate Your Fertilizer Plan: Based on the analysis, review your current or prospective fertilizer plans to explore if they will or still fit the soil’s needs. This is a perfect time to sit down with your local agronomist to explore product options.
- Check Mulder’s Chart for Antagonism and Synergisms: Review how applied nutrients to combat in-soil deficiencies can interact with other applied or in-soil nutrients. For example, if soils are low in nitrogen and excessive nitrogen is added each spring, it could limit the availability and uptake of key micronutrients like boron and copper.
- Integrate Practices: Combine your improved fertilizer plan with other appropriate management practices to enhance soil health, yield potential and sustainability.
Regular soil testing is an invaluable tool to help enhance nutrient use efficiency and subsequently yield potential. By understanding when to test, recognizing the benefits and knowing how to act on the results, growers can optimize yield potential and maximize ROFI.