So you’ve selected ESN as the right source for your nitrogen application…but now you need to determine the right rate, right place and right time. While the answers to these questions vary based on crop type, soil profile and geography, our team of agronomists are answering some of the most recent Ask The Agronomist questions covering application rates, blend percentages and fertilizer placement. Read their recommendations below, and don’t forget to submit your own question!
Question: Would using ESN reduce my total nitrogen usage rates?
Answer: That is a very common question we receive. Our research results do show that you can reduce rates and obtain the same yield level, however, this is not how we recommend using the product. ESN is more efficient as the name implies, but what our research has shown is that by keeping the total N rate the same, the plants will yield higher, and enough higher to more than offset the cost. View our application recommendations here.
Q: I am looking at trying some ESN this coming growing year. I am looking at using it as my split application of nitrogen. We apply urea in the spring before planting and incorporate it into the soil. I was curious if ESN could be mixed in with urea and incorporated in one application or if it needs to be applied in a separate application.
A: ESN can and is usually blended with urea and most other fertilizers, in fact I would say 90 percent of all ESN goes out in blends. ESN can be used preplant or as a top-dress also.
From your zip code it looks like you are in SE Minnesota. Probably some rolling hillsides and organic matter a little lower with karst soils and I will assume non-irrigated corn. In these scenarios you could possibly get by with a single application but split-applied may be a better fit based on my guesstimated soil type.
If you have a lot of acres and some are wet and harder to manage and you want to try the single application method, the blend would be best to be around 70 percent ESN and 30 percent urea. If you were to split apply, I have many folks who will try a couple different ways:
First application 60 percent ESN + 40 percent urea followed by 40 percent ESN + 60 percent urea (ends up being a 50/50 blend on the field) or straight urea or UAN. Putting ESN in the first pass is probably the most important as this is the nitrogen that will need protection for the longest period and the biggest leaching events usually are in the first half of the growing season. By having a high enough rate of ESN early you can have some assurance that if the weather turns against you when it is time to top-dress you have protected nitrogen already in the field to get you through the bad conditions (windy, wet) that can delay your second shot.
Q: I am planting a 60” corn plot this year and wondering about putting the nitrogen down primarily as ESN in a 2×2 band. Just wondering safe rates and thoughts. Fertilizer mix would have a little urea perhaps and some P&K with micros. My typical nitrogen rate on 30” row corn is about 120 lbs. for a 150 bu corn crop which I have been adding 20-30 percent as ESN.
A: If your equipment can assure a 2-inch separation between seed and fertilizer, you should not really be limited in the safe rate. If a clear separation is somewhat uncertain, the question is harder to answer. I have myself in trials used much higher rates than you are considering for 2×2 placement without damage.
For pre- or at-plant applications of ESN on corn, we recommend 70-90 percent of the total nitrogen as ESN. This will give you some immediately available to start the crop off with the bulk being released as ESN over the period of vegetative growth into the critical reproductive stages. Using such a blend, with a little urea and/or ammonium sulfate with your P&K, you should not have worries about safety in a 2×2 placement. The urea and potash would be the greatest concern, but your urea portion will be fairly small.
I like your plan; I like banding fertilizer close to the row when equipment and soil permits. We have excellent results with banding ESN near or below the row in corn studies.
One of our research cooperators, Dr. Fred Below, University of Illinois, has been applying ESN in trials at a depth of six inches directly below the corn row at rates as high as 180 lbs. N/acre without any stand effects and very good yield response. Urea at the same rate in the same placement has sometimes caused some damage.
Have a question that you didn’t find here? Submit your questions here, or give us a shout on Twitter, @smartnitrogen. We look forward to hearing from you and answering your questions about ESN Smart Nitrogen.
Disclaimer: This information is not intended to be complete or detailed use recommendations for all geographies, crops, or applications. User assumes all responsibility for proper use and handling for specific geographies, crops, and applications. Please consult ESN recommendations and/or your Nutrien ESN representative for complete recommendations for use. Consult ESN recommendations for more information.