Urea fertilizer represents a critical component in current agriculture and is a key supporting pillar of the growth in crop yields seen across different agricultural production systems around the world. The high nitrogen content of urea fertilizer is critical for improving the protein synthesis in plants and, in exchange, the protein content is known to affect the growth rates of plants and their productivity. Knowing how to use urea fertilizer optimally is therefore key to maximising agricultural production with minimal environmental impact.
Urea, a synthetic organic compound that combined carbon and hydrogen to form an ammonia derivative, is inexplicably cheaper, contains a higher percentage of nitrogen, and is far easier to handle than the other fertilizers on the table. When applied today, its yields multiply as they feed the exact nutrients that plants need to grow. According to Dr Emily Tran, an agronomist and expert in soil science, ‘Applying the right amount of urea fertilizer can improve the potential of crops to assimilate nitrogen, hence enhancing the sustainability of crop production.’
The use of fertilizers like sound urea application can ensure that food production becomes more sustainable as a whole and will be the theme of this post as we all get acquainted with urea and put into perspective why it is important in agriculture, and very importantly, how to apply and use it right for a good agricultural yields and environment. For when we talk about sustainable agriculture, it is important that both the yield maximisation and environment factors are addressed. On the flip side, it has some side effects. Because urea is highly soluble in water it has the tendency to leach deeper into the soil through percolation. This could result in its draining down into the ground or falling underground when water seeps through soil to supply the plant its needs.
Understanding Urea Fertilizer
Urea is a synthetic nitrogen-rich compound containing around 46 per cent nitrogen that serves as a major source of nutrition for plants to grow and develop. This is why it is valued so much in agriculture since it provides such a concentrated dose of nitrogen.
The molecules that make urea are the elements carbon, nitrogen, oxygen and hydrogen. To represent that in a simple way like a chemical equation we write CO(NH₂)₂. After urea is applied to the soil, the enzyme urease converts the urea into ammonium bicarbonate through a process called hydrolysis (a splitting with water), releasing nitrogen in a form that plants can take up.
Nitrogen affects plant growth at the deeper level provided by physiological and biochemical processes too. As Harish Patel, Ph D, a renowned soil scientist, tells us, ‘nitrogen is the basic constituent of amino acids involved in protein synthesis. Without sufficient amount of nitrogen, plants cannot synthesise proteins which are essential for plant tissue development and energy production’. This is why nitrogen from urea is most important; it helps build plant structure through the green plants’ photosynthesis. Photosynthesis is the act responsible for making all the tissues of plants which then produce surplus biomass. This is how crop yields improve on the farms.
To use urea efficiently, we need to understand how it works in the soil. When you apply simple urea to the soil, without any modification, it can move freely in the soil due to its high solubility. That can be a good or a bad thing depending on where it goes. If it goes into the plants’ roots, it’s good for them and also good for the agronomic sustainability of soils. However, if it goes elsewhere, it can lead to environmental pollution through either loss of nutrients via leaching or to the atmosphere via volatilisation. In that case, you have done something wrong. If you know when you are going to apply the fertilizer, and you know what the loss mechanisms for water and air are, then the timing of application and the soil conditions become important factors.
Preparation for Applying Urea Fertilizer
Before a farmer spreads urea, soil health and nutrient needs should be fully assessed. Urea fertilizer use therefore needs to be managed in order to match application to those needs and thus maximise effectiveness while minimising waste. Soil testing is conducted to determine the amounts of nitrogen and other vital nutrients needed – as well as pH and organic matter – to meet the demands of the crop, and to ensure that rates of urea fertilizer are not applied higher than the soil can handle.
Knowing the optimal time to apply urea is vital for maximising nitrogen uptake by the crop. The ideal time of application depends a lot on the crop in question and the prevailing weather. If applied at a time when the land has been sodden by rainfall, say, urea won’t dissipate into the soil or surrender its nitrogen to the atmosphere through volatilisation. The urea will be washed down to the soil, and will be converted into plant-usable forms by bacteria faster since the soil is damper and there is moisture in the air too. While this is a good practice, ‘Applying urea right before rain is beneficial because this increases the time period for urea dissolution which in-turn minimises nitrogen losses,’ caution Laura Gomez, a plant nutrition specialist, but ‘Heavy application of urea during a dry/windy condition will result in significant N losses’.
Arming oneself with the right tools and equipments (eg, broadcast spreader for an open field and hand-held spreaders for smaller spaces) can also help in its application. This would enable farmer to evenly distribute urea pellets on the soil. By calibrating applicators, the right amount of urea can be used. Farmers should also protect their safety during applications by wearing gloves and masks to prevent the fertilizer from entering to their nasal passage or mouth, and from direct contact with their skin.
If a farmer plans properly by conducting soil assessments, being mindful of the time of fertilizer application, and in order to use the right-size tool, it can increase the likelihood of a more productive use of the urea fertilizer. At the same time, it will not only be good for the plants and yield, but also for the environment – should there be any excess nutrients left, they won’t end up running down the gutter as pollution, or out into the atmosphere as greenhouse gases.
Detailed Steps on How to Apply Urea Fertilizer
With the proper application of urea fertilizer, farmers can take advantage of its benefits for their products while also ensuring that they are not adversely affecting the environment. The following steps will help you understand how to apply urea fertilizer correctly.
- Timing of Application: The most critical timing of urea application is to apply the fertilizer when the plants are actively growing and therefore able to utilise the nitrogen right away. This is most often done early in the season when the plants are small, shortly after planting, just prior to rapid growth stages, or late in a day or in overcast conditions to reduce losses from volatilisation.
- Soil Moisture Consideration: Apply urea when the soil is moist and lightly water, if possible, soon after application. This promotes incorporation into the soil more rapidly and reduces overall nitrogen loss to the atmosphere.
- Application: Spread evenly with a calibrated spreader, with spreader settings adjusted according to manufacturer’s specifications. For urea granules, a walk-behind spreader yields the best uniform coverage, so walk regularly in straight rows to give the spreader the best opportunity to distribute weed killer evenly across the entire field.
- Dosage and Distribution: Carry out modified prescription incorporating urea at the rate recommended by your soil test results. Do not apply more ammonium than recommended (anything above 200 lb N/acre) or you risk excessive vegetative growth and possible leaching through percolation into the groundwater. Also keep in mind improved management techniques like banding (applying urea in band on each side of a crop row) or side-dressing (applying urea to the side of the plants) can improve the effectiveness of N uptake by plants.
- For incorporation into the Soil: If feasible, lightly till after application to mix the urea into the soil. This step is key to reducing volatilisation and rushing it toward conversions that yield the plant-absorbed ammonium forms.
Do not apply urea on windy days. Keep in mind that urea is volatile. Urea is quickly lost as gas to the atmosphere, especially in dry, hot and windy conditions. Do not apply urea on water-logged soils. Nitrogen efficiently moves under these conditions but nitrogen can be lost to denitrification, where nitrogen is lost as gases to the atmosphere. Do not leave urea on the surface of the soil and do not leave urea on the surface of the soil for an extended period of time.
Following these steps will help to ensure that urea fertilizer is sidedressed and broadcast in the most efficient way, encouraging maximum crop yield and minimising environmental risk. However, remember that these are general principles, and that the conditions on your farm may require you to adapt them.
Best Practices for Urea Fertilizer Application
If we can follow the best practices for using urea fertilizer and adopt a sustainable alignment between them, it is possible to reap maximum benefits from the urea fertiliser while reducing its potential environmental risk.
- Timing and environmental conditions: Basically, applying urea when it is cooler will reduce the possibility of volatilisation. Early morning or late evening are the ideal times. You might also want to check the weather report for the next few days and try to avoid applying when heavy rain is forecast. This will ensure that at least some of the urea applied is absorbed by the plants.
- Minimisation of Nitrogen Loss: For reducing Nitrogen loss through volatilisation, you may use urease inhibitors. Since they slow down conversion of urea to ammonia, it will take longer for urea to convert to ammonia. It will afford more time to fertiliser to be incorporated in the soil, towards a better outcome. Dr Richard Feldman, an author from the Mississippi-based Cotton Physiology and Metabolism Lab and an expert in Soil Health, shares, ‘Incorporating urease inhibitors, especially in regions which experiences major volatilisation, is a major transformative step, will make it available to the crop for a larger time.’
- Interoperability with Other Fertilizers and Agronomic Practices: Blending urea with other fertilisers, such as phosphorus and potassium, helps provide more balanced nutrient supplies for crops. Applying urea along with other agronomic practices, such as crop rotation, regrowth and intercropping, can augment soil health and nutrient availability.
- Application Technology: Application techniques other than the usual spray or broadcast application can greatly improve the use efficiency of urea. The drip irrigation system systems can be modified with fertigation, in which urea is dissolved in water and dripped into the root zone of plants. Thus, not only use efficiency of urea is improved, it also helps save water.
- Soil testing and monitoring: Regular tests of soil status will help determine whether or not it is fertilizer-limited (the presence of nutrient deficiency will prompt fertiliser application) or fertilizer-excessive (determined when ‘elements of concern’ in the soil are above recommended levels according to the fertilizer recommendations).Portions of the primary nutrient ions, such as nitrogen and phosphorous, may all be above the threshold so the farmer will want to apply less urea; conversely, if the soil phosphoric acid level is low, the farmer may choose to apply a phosphate during the urea fertilisation.Monitoring of soil pH is important too, as soil acidification accelerates urea volatilisation: if the soil is too acidic, lime can be easily applied to lower it and improve urea use.
By adopting these practices, farmers can deliver the best yield per kilogram of fertilizer applied, then tailor the rest of the fertilizer to their crops’ needs in a way that minimises harmful environmental outcomes and keeps the soil productive for the next season.
Monitoring and Adjusting Post-Application
Now here we come to the difficult part: after applying urea, you need to monitor crop response to determine whether you need to alter your application strategy before possible negative effects on the environment occur.
- Monitor your crops: Notice the responsiveness of your crops to the application of urea. This can be observed by checking for signs of shoots having access to adequate amounts of nitrogen (a happy uptake system!), including increased foliage colour and vigour, and increased especially dark green growth, such as maybe in the lower leaves of an urea-responding plant. By contrast, if foliage appeared yellow or stunted, it might be a sign of inadequate nitrogen availability, and a reason to return to your fertilisation formula and figure out what was missing.
- Re-Sampling Post-Application: Obtain additional soil samples after the urea has been applied and incorporate it into the soil, and then after it begins to break down. This will help you determine how much nitrogen remains available out there in the soil and whether it’s time to top up. ‘Soil-testing after fertilisation can provide much needed information to guide refinements to ongoing nutrient management so that crops receive only what they require,’ says Thomas Green, an agricultural consultant.
- Response-Based Adjustments to Application Strategy: Use the information on crop response and soil test results to make adjustments in application strategy. For example, if crops weren’t performing due to low moisture, but the nitrogen test was high, 200 lbs, you might try to water a little deeper or longer. Or if the crops aren’t performing based on the nitrogen response but the soil test was low, 50 lbs, you might not be getting good nitrogen availability in the soil; in this case I would confer with an agronomist to make a nitrogen application on the potassium and magnesium I applied. Try an experiment to manage more strategic or precise nitrogen investments.
- Monitoring the environment: Local water bodies should be monitored for effluents from runoff, especially following heavy rain. Buffer zones and slow-release nitrogen formulations reduce the danger of runoff.
- Long-Term Management Plan: Long-term fertility plan with crop rotation, use of cover crops, periodic amendments (eg, organic matter)Improving soil health and fertility through cover crops, crop rotation and periodic amendments to restore organic matter all increase a farm’s nutrient retentive capacity for urea fertilizer.
Monitoring and adapting fertilizer inputs to real-time data and crop responses allows to use urea fertilizer as efficiently as possible to get the highest possible yield of crops while maintaining high quality environment.
Conclusion
To sum up, the ability to use urea fertilizer correctly is very important. This way you can get the most benefit from it, and the crops can grow. This is the right way to use this miracle element. All you have to do is remember or learn how this element acts. You must prepare for the use of urea fertilizer. It’s important to monitor how the crops grow and how to react promptly to the negative effects of a high concentration of nitrogen.
In conclusion, the following strategies can help to apply urea successfully: appraising soil condition and status, applying fertilisers at the right time, applying fertilizers by right method, avoiding N loss, using urea with other farming system. Moreover, short-term or seasonal fertilizers/ fertilisation methods need to be modified on the basis of crop and soil feedback in order to adapt the needs and realities that result due to environmental changes.
‘The best and correct use of urea fertilizer is an integral part of a sustainable agricultural system, not selfishly hoarding nature’s gifts at the expense of future generations,’ explains Dr Sarah Johnson, a veteran expert in sustainable agriculture. With the help of new methods, based on numerous centuries of trial and error, the farmers will continually improve so that they can produce plants profusely without damaging our planet.
Thus, this approach highlights the need to find a common ground between providing the best possible food production and, on the other hand, conserving environmental integrity, ultimately resulting in a more productive and sustainable agricultural landscape.
References
Loyal Extend Release Polymer-coated Urea fertilizer 40days/60days/90days/120days:The Loyal Advanced 60-Day Polymer-Coated Urea, is an innovative slow-release fertilizer designed for extended nutrient delivery, making it ideal for promoting sustained growth in agricultural and horticultural applications.
Chemical Transformations: Urea undergoes significant chemical transformations once applied to the field, primarily converting to ammonium bicarbonate. This process is facilitated by the enzyme urease and usually completes within 48 hours under field conditions.
Application Methods: The most effective way to minimize nitrogen loss when using urea is to incorporate it into the soil rather than leaving it on the surface. This can be achieved through irrigation, rainfall soon after application, or mechanical incorporation like plowing or banding.
Seasonal Considerations: Timing is also critical. In colder climates, applying urea in cooler temperatures can reduce the rate of volatilization. Conversely, in warmer and more humid climates or seasons, the risk of volatilization increases, so immediate soil incorporation is essential to prevent nitrogen loss.
Crop Specifics: The effectiveness of urea also varies depending on the crop. For instance, crops like corn, which have a more extensive root system, can utilize nitrogen more efficiently if the urea is applied properly and at the right time. In contrast, shallow-rooted vegetables might require different nitrogen management strategies to ensure adequate nitrogen supply without causing damage from high ammonium levels.
