A guide to sidedressing: Delayed nitrogen application and yield improvement

Posted on 01/05/2017 in Featured, Planting, Sprayer.

4Rs of Nutrient StewardshipImprove your growing season by applying nitrogen to your crops when and where it matters most. When you add sidedressing to your operation, your crops will have enough nitrogen to optimize your yield and profitability. Most nitrogen is used by the crop during its initial growth, as sidedressing enables maximum growth and yield by replacing nitrogen lost during that initial crop growth period. However, there are some instances that encourage nitrogen application after the corn has already emerged. Below are some best practices if you are considering delayed sidedressing and nitrogen application:

Sidedressing Do’s and Don’ts

  • DO sidedress soil that has lost nitrogen between April and June
  • DO sidedress on well-drained, sandy soils and heavy-textured, poorly-drained soils
  • DO NOT sidedress unless there is early season nitrogen loss

Advantages of sidedressing and delayed nitrogen application

  • Increases use of fertilizer by the crop
  • Utilizes pre-plant application time for corn planting

Disadvantages to delayed application

  • Less time to complete application
  • Dry, unpredictable weather wards off surface-applied nitrogen, making it unavailable to crop

Earliest time for nitrogen sidedressing

  • As early as you can enter your field without injuring young corn (often between 4 to 6 inches tall or 4 to 8 leaf stage)

Latest time for nitrogen applications

  • Before the 8-leaf stage, as corn utilizes nitrogen most during its grand growth stage; apply before the 10-leaf stage for most hybrid corns

Best nitrogen source

  • Ammonia or nitrogen solutions knifed in
  • Ammonium nitrate over top of crop
  • Granular urea, if clean and tilled

Note: Both granular and urea and ammonium nitrate broadcast in standing corn will cause some foliar burn. Nitrogen solutions should not be sprayed directly on foliage, as it will cause extensive burn.