Optimizing Sidedress Nitrogen for Corn: 3 Essential Tips

Table of Contents

1. Introduction
2. Consideration 1: Application Equipment and Type of Fertilizer
   • 2.1 Pros of Own Application Equipment
   • 2.2 Pros of Custom Application
   • 2.3 Cons of Custom Application
3. Consideration 2: Amount and Timing of Sidedress Nitrogen Application
   • 3.1 Benefits of Sidedress Nitrogen Application
   • 3.2 Soil Texture and N Loss Risk
   • 3.3 Nitrogen Application for Corn on Corn and Corn Following Soybean
   • 3.4 Best Time to Sidedress Nitrogen
4. Consideration 3: Use of Urease Inhibitor
   • 4.1 Importance of Rainfall or Irrigation After Urea Application
   • 4.2 Risks of Urease Inhibitor Use
5. Conclusion
6. FAQ

💡 Highlights:

• Split application of nitrogen fertilizer for corn has increased in popularity.
• Three key considerations for determining sidedress practices.
• Pros and cons of owning application equipment.
• Benefits of split application on lighter textured soils.
• The best time to sidedress nitrogen in Minnesota.
• Risks and benefits of using a urease inhibitor with urea application.

Introduction

Corn farmers have been increasingly adopting split application techniques for nitrogen fertilizer in recent years. This approach offers several advantages but also requires farmers to make important decisions regarding application equipment, timing, and the use of urease inhibitors. In this article, we will discuss the key considerations for determining the best-sidedress practices for corn farming.

Consideration 1: Application Equipment and Type of Fertilizer

When deciding on the sidedress practices, it is essential to consider who will handle the application and the available equipment. Many farmers have invested in their own application equipment, giving them more control over the type of fertilizer and its placement. Using a spin spreader for in-season application is often the fastest method, but not all farmers have the capability to apply top dress urea themselves. Custom applications, done by fertilizer dealers or custom applicators, may be a viable option but come with equipment limitations. Each type of application has its advantages. For example, urea is generally cheaper than UAN, and farmer-owned self-propelled sprayers allow for timeliness, quality control, and economic advantages.

2.1 Pros of Own Application Equipment

• Control over type and placement of fertilizer.
• Fast in-season application with spin spreader.
• Timeliness, quality control, and cost advantages with farmer-owned self-propelled sprayers.

2.2 Pros of Custom Application

• Opportunity to utilize equipment options available in the area.
• Access to different types of fertilizers.
• No need for investment in application equipment.

2.3 Cons of Custom Application

• Limited equipment options.
• Higher reliance on external parties for application timing and quality control.

Consideration 2: Amount and Timing of Sidedress Nitrogen Application

The second decision that farmers need to make is the amount of nitrogen to be applied as sidedress and the optimal timing during the growing season. Research projects have consistently shown that lighter textured soils benefit from a higher proportion of nitrogen applied as sidedress. This is because spring pre-plant applications on such soils have an increased risk of nitrogen loss. However, in finer textured soils, the cost-effectiveness of split applications may vary depending on the potential for nitrogen loss. Split applications have been found to be more beneficial in excessively wet years or areas of the field prone to waterlogging after rainfall. When planting corn on corn, a higher rate of pre-plant nitrogen application is recommended due to temporary N immobilization caused by high residue levels.

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