Urea fertilizer is one of the most widely used nitrogen sources in global agriculture, valued for its high nitrogen content, cost-effectiveness, and ease of application. Whether you’re managing a large-scale farming operation or a home garden, understanding how urea fertilizer functions in the soil can significantly enhance your crop yield and nutrient efficiency.
Chemical Structure of Urea Fertilizer
Urea (chemical formula: CO(NH2)2) is an organic compound composed of 46% nitrogen, making it the most concentrated solid nitrogen fertilizer available. Its molecular structure includes two amine groups attached to a carbonyl group, which allows it to release nitrogen rapidly once it interacts with soil moisture and microbial enzymes.
| Compound | Formula | Nitrogen Content |
|---|---|---|
| Urea | CO(NH2)2 | 46% N |
This high nitrogen content explains why products like SULPHOMIN (45% nitrogen with sulfur and organic matter) are excellent supplemental solutions when quick and sustained nitrogen availability is needed.
Breakdown Process of Urea Fertilizer in Soil
Once applied, urea undergoes a hydrolysis process catalyzed by the enzyme urease. This reaction converts urea into ammonium carbonate, which then dissociates into ammonium (NH4+) and carbonate (CO3²?).
The breakdown stages include:
- Urea hydrolysis:
- CO(NH2)2 + H2O ? 2NH3 + CO2
- Ammonia to ammonium conversion:
- NH3 + H2O ? NH4+ + OH?
This reaction raises soil pH temporarily around the granule, which can lead to nitrogen loss through ammonia volatilization if not managed properly.
READ MORE: Urea Fertilizer: The History and Development
Urea Fertilizer and Nitrogen Availability to Plants
The ammonium (NH4+) produced from urea is readily available to plants or is further oxidized by nitrifying bacteria into nitrate (NO3?), which is the most mobile and preferred form for many crops.
To support nitrogen uptake, you can use Ugarit 40-10-10 + TE, which provides high nitrogen along with balanced phosphorus and potassium for robust vegetative growth. Products like Biofast, rich in humic and fulvic acids, also enhance nitrogen availability by improving root absorption and soil microbial health.
Here are a few practical strategies to ensure nitrogen from urea fertilizer is efficiently used by crops:
- Incorporate urea into soil to minimize volatilization.
- Time application with irrigation or rainfall to promote conversion.
- Split applications during key growth stages to match crop demand.
READ MORE: How Nitrogen Fertilizer Works: A Simple Guide for Farmers and Gardeners
Interaction of Urea Fertilizer with Soil Microbes
Soil microbes play a vital role in transforming nitrogen from urea into plant-usable forms. Urease-producing bacteria initiate the conversion of urea to ammonium, while nitrifying bacteria like Nitrosomonas and Nitrobacter convert ammonium into nitrate through nitrification.
Using microbe-friendly formulations like Ugarit 10-0-5 + 70% Organic Matter (Humic + Fulvic) supports microbial activity, enhancing nitrogen mineralization. Additionally, CALCIMAG, which contains nitrogen, calcium, and magnesium, helps balance soil pH and nutrient ratios, further optimizing microbial function.
Key microbial interactions include:
- Urease activity: Catalyzes hydrolysis of urea.
- Nitrification: Converts NH4+ to NO3?.
- Denitrification: Occurs under anaerobic conditions, causing N loss as N2 or N2O gases.
Factors Affecting Urea Fertilizer Efficiency
Several environmental and soil conditions can influence the efficiency of urea fertilizer:
1. Soil pH
Alkaline soils (pH > 7.5) increase the risk of ammonia volatilization. In such cases, combining urea with acidifying products like SULFOMIX (11% sulfur) or Sulforex 60 + Cu helps reduce nitrogen losses.
2. Temperature and Moisture
High temperatures accelerate urea hydrolysis, increasing volatilization. Proper irrigation or rainfall incorporation is essential after application.
3. Soil Texture and CEC (Cation Exchange Capacity)
Sandy soils with low CEC have poor nitrogen-holding capacity. Using stabilizers or organic-rich blends like Ugarit Multi (with calcium and sulfur) can help retain nutrients in such soils.
4. Application Method
Broadcasting urea without incorporation can result in high nitrogen loss. For improved outcomes:
- Apply urea during cooler parts of the day.
- Combine with nitrification inhibitors if not incorporating immediately.
- Use controlled-release blends when feasible.
5. Crop Type and Growth Stage
Different crops have varying nitrogen needs. Specialty products like Ugarit Cereal (N 15%, Cu 2%) are tailored to cereals, offering both nitrogen and micronutrients for chlorophyll production and tillering.
READ MORE: Urea Fertilizer: A Key Nitrogen Source for Modern Agriculture
Actionable Practices to Maximize Urea Fertilizer Benefits
To ensure you’re making the most of your nitrogen inputs, consider the following techniques:
- Soil testing before fertilization to understand baseline nitrogen levels.
- Split applications aligned with crop demand.
- Use of organic matter, such as humic substances in Biofast, to improve retention.
- Foliar feeding supplements like Ugarit 27-27-27 + TE during critical growth periods.
Recommended Products for Optimized Urea Fertilizer Use
To complement and enhance the effects of urea fertilizer, here are several YaraFert product recommendations:
- SULPHOMIN: Liquid fertilizer with 45% nitrogen and 15% sulfur, ideal for fast nitrogen uptake.
- Ugarit 10-0-5 + Organic Matter: Granular blend with humic and fulvic acids to stimulate microbial activity and root development.
- Biofast: Gel formula combining balanced NPK and 24% humic + 24% fulvic acids to increase nitrogen absorption and root efficiency.
- CALCIMAG: Provides nitrogen with calcium and magnesium to maintain nutrient balance in acidic or sandy soils.
- Ugarit 40-10-10 + TE: High-nitrogen suspension with trace elements, perfect for early vegetative stages.
Final Thoughts
Urea fertilizer plays a critical role in modern agriculture, offering a high-efficiency nitrogen source to support plant growth and productivity. By understanding the chemistry, microbial interactions, and environmental factors influencing its behavior, you can optimize its use and minimize waste.
Whether you’re growing cereals, vegetables, or fruit trees, integrating scientifically formulated products like YaraFert Ugarit, SULPHOMIN, or Biofast into your fertilization plan ensures maximum nutrient efficiency and crop health.
Ready to take your nitrogen management to the next level?
- Explore our full range of YaraFert nutrient solutions tailored to every crop stage.
- Contact our agronomy team for customized application plans.
- Visit our website to download nutrient management guides and product datasheets.
Empower your farm with science-backed solutions—because every gram of nitrogen counts.