A bag of urea with urease inhibitor costs more than a bag of regular urea, and that premium is paid at the counter, right away, for every kilogram you load onto the truck. An additional entry into the field to split the fertilization into one more application costs labor, fuel, and coordination, and is paid later, spread out in the payroll. These are two ways to pay for the same thing, and almost no one puts them on the same sheet to compare them. Keep the idea of the premium per unit of nitrogen in mind, because in the end, we turn it into a calculation with numbers.
The previous blog of this season left a round figure: moving one hundred kilograms of fertilizer from one date to another, without changing the total or the product, resulted in nearly nine percent more yield. What that calculation does not cover is what happens in the three or four days following each application. You can hit the week with calendar precision and see how part of the bag goes into the air before the root can take it, and against that, the date has nothing to offer. That stretch is decided by three other things: the source you bought, the way you put it in the ground, and whether you also paid a premium for some technology to make the nitrogen last a little longer.
That nitrogen is lost in the journey between the bag and the root is no news to anyone, and as we already addressed in our blog You Apply Kilograms of Nitrogen and the Crop Keeps Asking, the Difference Between Fertilizing and Knowing How Much to Fertilize, which you can read here, that’s where a good part of what you paid stays. What is worth looking at slowly is the market that has been built around that journey, with additives, coatings, and stabilized formulas that cost more per kilogram, and knowing which of all that is paid for on your farm and which is not.
What You Buy When You Buy Technology is Time
It is advisable to translate the three families of products into a single unit, and that unit is time. You are not buying efficiency in the abstract; you are buying days.
A urease inhibitor buys days between application and the hydrolysis of urea. What it does is delay the transformation of urea into ammonium, so that if it rains or you irrigate during those days, the nitrogen has time to move into the soil before being exposed. It does not eliminate anything; it just runs the clock. A nitrification inhibitor buys days of permanence in ammonium form, delaying the conversion to nitrate, which is the form that leaches. And a controlled-release source buys weeks because the coating gradually delivers the nutrient.
This translation completely changes the commercial question. It is no longer which product is better, but how many days you need and what is the cheapest way to get them on your farm. If you can irrigate or have rain forecasted within two days, you already have the days that the inhibitor would sell you. If your field is forty minutes away and an additional entry costs a full day’s work, the weeks that a coating buys may turn out to be cheaper than the past.
The Additive Moves a Few Points, the Source Moves the Order of Magnitude
Here is the data that most annoys the counter, and it comes from a trial over two consecutive coffee campaigns, with doses ranging from zero to four hundred fifty kilograms of nitrogen per hectare and six fertilizations per cycle.
Conventional urea lost 22.0 percent of the applied nitrogen at the 150-kilogram dose and 22.8 percent at the 400-kilogram dose, which at the end of the six fertilizations meant 66 and 182 kilograms of nitrogen per hectare that did not reach the plant. Urea with urease inhibitor lost 16.9 and 19.8 percent at the same doses, meaning it avoided the loss of 15.9 and 24.3 kilograms per hectare compared to regular urea. That is a real and measurable improvement, and at the same time, it is an improvement of just a few percentage points.
The same body of work measured other sources under coffee conditions, and there the result is of another nature. Ammonium nitrate lost less than one percent of the applied dose, regardless of the weather conditions at the time of fertilization. In the comparisons of the review of technologies for nitrogen fertilization in coffee, urea with inhibitor was at 14.5 percent and urea with copper and boron at 13.5, while ammonium sulfate was at 0.6 percent and ammonium nitrate at 0.5.
The practical reading is brutal in its simplicity. The additive on urea moves the loss from twenty-two to seventeen percent; changing the source moves it from twenty-two to less than one. Before paying a premium for an additive, the question that matters is whether in your case you can simply use another source, considering price per unit of nitrogen, local availability, effect on soil pH, and sulfur contribution. Ammonium sulfate acidifies more than urea, which matters a lot if you’ve just read about aluminum saturation, and it contributes sulfur, which is short in many coffee fields. Ammonium nitrate has handling and access restrictions in several markets. I am not saying that the answer is always to change sources; I am saying that this alternative almost never appears in the conversation because no one makes an extra margin selling it.
Controlled Release, the Fractionation That Doesn’t Require One More Pass
Of the three families, the controlled release one is the most similar to what you were already doing when you were fractionating, and that’s why it’s worth breaking it down separately.
The polymer coating delays and extends the delivery of nitrogen. In characterization studies, coated formulations ran the peak release of nitrate from around thirty days to nearly seventy days after the initial moisture. And meta-analyses in annual crops report increases in nitrogen use efficiency of around twenty-four percent compared to conventional urea at the same dose, with less leaching and lower volatilization. The most recent review on novel fertilizers, which examined one hundred twenty-six studies, confirms that polymer-coated urea is the most proven technology in the group, with sixty-six of those studies dedicated to it.
What’s interesting is how that reads in terms of the farm. A controlled-release source is, in practice, a fractionation that is already done within the granule. The previous blog showed that loading the fruit expansion window and splitting that fraction into more frequent applications produced the improvement, and noted that in manual application, the reasonable ceiling is three or four moments, because each entry costs. The coating is the way to achieve the effect of more entries without making more entries.
There lies its risk, and it is not minor. If you buy the wrong release curve, the technology works against you. A coating that delivers its peak at seventy days applied eight weeks before the maximum demand window will arrive just in time; applied in the window, it will deliver a good part of its load when the demand has already decreased, which is exactly the mistake that the previous blog identified as the worst of all. The question to ask the seller is not how long the product lasts, but in how many days it delivers its peak and at what soil temperature that was measured, because the release of the coatings depends on temperature.
Knowing Which Source Was Applied to Each Lot
Can you today, lot by lot, say which nitrogen source was used in each application of the year, on what date, whether there was rain or irrigation in the three days following, and what that lot yielded at the close? Without that series, any evaluation of an efficiency technology becomes an impression, and the impression always favors the product that the supplier visited most often. Harvis helps you record the source, dose, and date of each application by lot, cross-reference that with rain and irrigation events, and compare at the end of the campaign the yield and cost per unit of nitrogen between the lots that used one source and those that used another, so that next year's purchasing decision comes from your numbers. Contact us and we’ll set it up over the lots you already have defined.
The Incorporation, the Technology That No One Bills
There is an intervention that reduces loss comparably to an additive, has no premium, and does not appear in any catalog.
In comparisons of sources and management in coffee, urea dissolved in water lost 4.2 percent, compared to granulated urea applied dry. That data puts incorporation above any additive evaluated in the same work, and incorporation is not bought; it is done. Burying the fertilizer, applying it in a covered band, or irrigating immediately after application are ways to achieve the same effect that the inhibitor promises, with labor cost instead of product cost.
This has a consequence of order in decision-making. If you still apply urea on the surface and do not irrigate afterward, buying an inhibitor is paying for a partial remedy to a problem that your application method is creating. First, solve the incorporation, which is free or almost, and only then evaluate if there is a gap worth filling with product. Studies on nitrogen use efficiency in coffee according to application method have been pointing out the same for over a decade, and it remains the last thing to adjust in practice.
It is worth the inverse warning, because there are contexts where incorporation is not possible. In established hillside coffee plantations, in lots with leaf litter that you do not want to remove, or in broadcast applications over steep slopes, mechanical incorporation is not available, and there the additive or source change is indeed a reasonable path.
What the Label Must Say Before You Pay the Premium
A stabilized fertilizer is a product with an active ingredient, and as such, it is bought by reading what it declares, not trusting the adjective on the packaging.
The minimum that the label must include is the name of the inhibitor and its concentration, not just the word stabilized or the mention of a technology with a commercial name. Without those two pieces of information, you cannot know if the product contains the dose of inhibitor that the literature evaluated or a fraction of it, and efficacy depends on the dose. It must also include the registration that the health authority requires for fertilizers and conditioners, which is what gives you recourse if the product does not comply.
And there is a management point that almost no one mentions at the counter. The most used urease inhibitor is a molecule that degrades with heat and storage time, so a correct factory bag can arrive at your application being overpriced urea if it spent weeks in a hot warehouse or outdoors. The question about the production date and storage conditions is not a formality; it is part of what you are buying. Buy close to the date of use, store under roof and ventilated, and distrust a lot with a big discount and an old date.
When the Premium is Not Paid
The first limit is fertigation, which nullifies the coating business. If you already have drip installed, the cost of an additional application is marginal, so you can fraction as much as you want without buying anything. In that context, paying for controlled release is paying for a service that your system already provides, and the fertigation trial that provided the numbers from the previous blog is proof that fine fractionation in irrigation is where the return is.
The second limit is the condition that determines loss. Technologies that prevent volatilization perform where volatilization is high, that is, with urea on the surface, in soils with pH tending to neutral or alkaline, with high temperature and no water in the following days. In an acidic soil, under shade, with frequent rain and with incorporated application, the initial loss by volatilization is lower, and the margin for improvement of the additive shrinks. Paying the premium there is buying a solution for a problem that your context has already mitigated.
The third limit is the lag of the curve, which we already mentioned and is worth repeating as a purchasing warning. A coating whose release extends beyond the crop's demand window delivers nitrogen when the root has already decreased its consumption, and that reproduces exactly the error of applying late. Ask for the release curve with its reference temperature and compare it against the phenology of your lot before buying.
The fourth point is the premium calculation, which is what we saved at the beginning. The way to do it is straightforward. Calculate how much the unit of nitrogen costs in the conventional source and in the technology being offered, and find the difference per hectare at your actual dose. On the other side, estimate the value of the nitrogen that the technology would prevent from being lost, using the percentage points of improvement from the literature on your own dose, and add the cost of the entries into the field that the technology would save you. With the numbers from the coffee trial, the inhibitor avoided between sixteen and twenty-four kilograms of nitrogen per hectare depending on the dose; multiply that by your price per kilogram of nitrogen and compare it against the total premium. If the premium is greater than the sum of the saved nitrogen plus the saved labor costs, the technology does not pay off on your farm, no matter how good it is in the trial.
Two Strips, the Same Unit of Nitrogen, and Two Invoices
The exercise fits in one lot and one campaign, and the key is to equal what is almost never equalized. Choose a lot and divide it into two comparable strips in soil, age, and variety. Both will receive the same amount of nitrogen units in the year, not the same number of kilograms of product, because the sources have different concentrations, and comparing bags instead of units is the most common way to ruin the trial.
One strip receives your usual source and management. The other receives the alternative you are evaluating, whether it is an additive, a coating, a source change, or simply incorporating what you currently apply on the surface. I recommend starting with the last one because it costs nothing and moves the most points according to the data above.
Record in both strips the date of each application, the source, the nitrogen units, the product cost, the number of entries into the field, and the cost of those entries. And note the rain or irrigation in the three days before and after each application, because that data will explain any result that does not match.
At the end of the campaign, compare four numbers between the strips: yield, total cost per unit of nitrogen effectively applied, number of entries, and labor cost. The fertilizer in units was the same, so the difference comes from the source, management, and logistics, which is exactly what you wanted to measure.
Repeat a second year before changing the purchase for the entire farm. A single campaign can be dominated by the rainfall regime, and losses due to volatilization depend heavily on the weather in the days following each application.
Technology is Bought for What It Does with Time
The conversation about sources is often framed as a choice between modern and traditional, and that is a less useful way to look at it. All these technologies do one thing: run the clock between the moment the fertilizer touches the soil and the moment the root takes it. When you have another cheaper way to run that clock, with irrigation, incorporation, one more pass, or a different source, the premium is not justified by being modern. And when you don’t have it, because the lot is far away, the slope is steep, or labor is scarce, the premium may be the best deal of the campaign. The answer is not in the product; it is in the comparison.
What you can do starting Monday fits into five decisions. First, review how you apply, because dissolving or incorporating urea reduced loss to 4.2 percent compared to granulated on the surface, and that costs nothing in product. Ask for the price per unit of nitrogen and not per bag in each source offered to you, as it is the only way to compare apples to apples. Inquire about the name and concentration of the inhibitor, the production date, and the storage conditions, since the molecule degrades with heat and time, and an old bag is expensive urea. Before buying controlled release, ask for the release curve with its reference temperature and match it against the phenology of your lot, because a peak that arrives after the demand window reproduces the error of applying late. And set up the two strips with the same nitrogen units to have a figure of your own at the end instead of the brochure's. The producer who makes that comparison on half a hectare knows what source to buy next year and why; the one who decides at the counter will continue paying premiums that their context does not need, and labor costs that a product would have saved.
Do you want to have recorded the source, dose, and date of each application by lot, cross-referenced with rain and closing yield, to decide your purchases with your own numbers? Contact us via WhatsApp or schedule a demo, and we’ll show you how Harvis turns your tasks into that comparison.
Consulted References
- Ammonia volatilization from conventional and stabilized fertilizers, agronomic aspects and microbiological attributes in a Brazilian coffee crop system. (2023). Frontiers in Plant Science, 14, 1291662. https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1291662/full
- Technologies for Fertilizers and Management Strategies of N-Fertilization in Coffee Cropping Systems to Reduce Ammonia Losses by Volatilization. Plants. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9741429/
- Blending Controlled-Release and Urease-Inhibitor Technologies as Innovative Solutions to Reduce Ammonia Emissions in Coffee Environments. Soil Systems, MDPI, 7(4), 83. https://doi.org/10.3390/soilsystems7040083
- Urease inhibitors technologies as strategy to mitigate agricultural ammonia emissions and enhance the use efficiency of urea-based fertilizers. (2024). Scientific Reports. https://www.nature.com/articles/s41598-023-50061-z
- Review of research and innovation on novel fertilizers for crop nutrition. (2025). npj Sustainable Agriculture. https://www.nature.com/articles/s44264-025-00066-0
- Plasma-modified biodegradable coatings for controlled nitrogen release from urea. (2025). Scientific Reports. https://www.nature.com/articles/s41598-025-23866-3
- Optimizing controlled-release urea and urea combinations for sustainable production under nitrogen reduction. (2025). Frontiers in Plant Science. https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2025.1576049/full
- Controlled-release fertilizers, a review of agronomic and environmental performance. (2025). Journal of Integrative Agriculture, 24(1), 36–60. https://doi.org/10.1016/j.jia.2024.05.012
- Agronomic Assessment of a Controlled-Release Polymer-Coated Urea-Based Fertilizer. PMC. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8004158/
- Split application of polymer-coated urea combined with common urea improved nitrogen efficiency without sacrificing yield while saving 20% nitrogen input. PMC. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10875009/
- Agronomic efficiency of NBPT as a urease inhibitor, a review. Annals of Agricultural Sciences. https://www.sciencedirect.com/science/article/pii/S2090123218300638
- Sadeghian, S. y colaboradores. (2022). Determinants of nitrogen use efficiency in coffee crops, a review. Revista de Ciencias Agrícolas, 39(2). https://doi.org/10.22267/rcia.223902.183
- Salamanca-Jiménez, A., Doane, T. A. y Horwath, W. R. (2017). Nitrogen Use Efficiency of Coffee at the Vegetative Stage as Influenced by Fertilizer Application Method. Frontiers in Plant Science, 8, 223. https://www.frontiersin.org/articles/10.3389/fpls.2017.00223/full
- Optimizing drip fertigation at different periods to improve yield, volatile compounds and cup quality of Arabica coffee. Frontiers in Plant Science, 14, 1148616. https://pmc.ncbi.nlm.nih.gov/articles/PMC10272449/
- Nutrients Leaching in Response to Long-Term Fertigation and Broadcast Nitrogen. PMC. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7696231/
- Food and Agriculture Organization of the United Nations. Arabica Coffee Manual, capítulo de nutrición y fertilización. https://www.fao.org/4/ae939e/ae939e06.htm