The days are getting shorter, the weather is getting cooler and harvest is in full swing or even winding down in some areas. All these things cause us to start thinking about our nitrogen planning for the 2022 corn crop. What considerations should we keep in mind as we develop our plans for next year?

What did the 2021 crop tell you about your nitrogen strategy?

Did the crop offer any clues as you ran the combine through the field? Nitrogen deficiencies most often express themselves as “firing” on the leaf mid-rib from the stalk to the leaf tip. Ear tip-back may be another sign of nitrogen deficiency. Observing these symptoms might give you reason to reevaluate your nitrogen plan.

How did your nitrogen plan respond to the weather patterns of 2021?

Early spring rains in many areas were frequent and heavy. These heavy, drenching rains may have caused nitrogen loss due in part to leaching (loss of soluble nitrogen moving downward in the soil profile with water) or denitrification (loss of soil nitrogen in the form of nitrogen gas as a result of water-logged/anaerobic soil conditions). During the summer months, many areas experienced very dry soil conditions.

The lack of moisture may have prevented nitrogen uptake during critical growth periods, potentially reducing crop productivity. Both weather patterns may have had a negative impact on your corn crop and added a level of difficulty in diagnosing whether you had nitrogen deficiencies.

Did you implement a nitrogen management strategy with your 2021 corn crop?

The 4R principles (rate, source, time and place), multiple N applications and utilization of nitrogen stabilizers can all impact availability and efficient use of your applied nitrogen. The systems approach to nitrogen management may be advantageous from an economic and environmental standpoint. Nitrogen stabilizers are also an important part of nitrogen management as they keep nitrogen in a stable, ammonium form to protect from loss to the environment. Talking with your FS Crop Specialists about nitrogen-focused MiField trials can help answer many of your questions related to fields managed with multiple nitrogen applications.

What is the best way to determine the proper nitrogen rate for the 2022 growing season?

Yield-based recommendations, Maximum Return to Nitrogen (MRTN) and Predictive Modeling tools are all ways to determine the most efficient nitrogen rates for your individual situation.

  1. MRTN is a nitrogen guideline model based on corn response to nitrogen fertilizer applications across many years and locations, while also accounting for fertilizer and grain investments. The model provides a nitrogen rate and profitable range based upon crop rotation, soil productivity potential, current price of nitrogen, grain price and field history. Your FS Crop Specialist can help you determine your MRTN.
  2. Predictive modeling programs such as Climate Field View™ allow growers to input planned nitrogen programs, cropping practices, field information and weather patterns to forecast nitrogen utilization and availability.
  3. Yield Based = #N/bushel x yield goal

For the latest information on nitrogen management systems and Strategies talk with your FS Crop Specialist before you begin applying your nitrogen this fall or next spring. As a reminder, fall nitrogen applications should only be applied when soil temperatures are at or below 50 degrees at 4 inches.

Best of success on a safe harvest season.

Dana Hite and Robert Bennett serve as agronomy marketing managers at GROWMARK.