Is urea fertilizer really that great?

Is urea really as great as word of mouth? What do you understand about urea? Can urea really kill weeds? Please refer to this article of VNT to understand more.

What is urea?

Urea is a type of organic nitrogen fertilizer that provides the most popular N, accounting for 59% of all nitrogen fertilizers produced in countries around the world. Urea is the type of fertilizer with the highest N ratio, containing up to 45-47% N. With such a high N content, urea is considered the type of fertilizer that brings the highest economic efficiency in agriculture.

Urea usually exists in natural form because it is a component that appears in animal manure. In production, urea is the result of a reaction between ammonia gas (NH3) and carbon dioxide (CO2) under temperature and pressure conditions.

During production, two urea molecules can accidentally bond together to form biurea - a substance that is harmful to plants when urea is sprayed on leaves. The Biurea ratio is regulated to not exceed 1.5% according to Vietnamese standards. If this ratio is 2.5% - 3.1%, it can be toxic to plants.

Physical properties of urea fertilizer:

- Chemical formula: CO(NH2)2

- Melting point: 133°C

- Solubility in water: 1080g/1 liter of water at 20°C

- Humidity: ≤ 0.5%

- Purity: ≥ 99.5%

- Biurea: ≤ 0.99%

Appearance of urea fertilizer

Types of urea fertilizer on the market

Currently on the market, there are 2 types of urea fertilizer with similar quality:

– White crystalline urea fertilizer, round grains, very soluble in water. This type has the disadvantage of strongly absorbing moisture, making it difficult to preserve in high humidity environments.

– Pelleted urea fertilizer, small as fish eggs. This type has an additional moisture-proof ingredient, so it is easy to preserve even in high humidity environments, during transportation. Due to this superior feature, it is chosen by many people for use in farming and agricultural production.

Types of urea fertilizers on the market

Applications of urea fertilizer for crops

Urea fertilizer has countless wonderful applications and is especially necessary for crops

– Provides high levels of N for the growth and development of crops. Urea can be applied to plants by mixing or sprinkling on the surface. Thanks to its high solubility (1080g/1 liter of water at 20°C), urea easily dissolves in water to form a liquid form to add to irrigation water or can be sprayed on leaves. Plants can absorb it easily.

– Urea fertilizer does not leave any excess or harmful residue like other fertilizers except for the ammonium that can be washed away into water. Easily soluble, does not harm the leaves of plants. This is the reason why urea is more suitable for spraying on leaves and for irrigation than other nitrogen fertilizers.

– After being applied to plants, urea will be absorbed into the soil or plants, naturally available enzymes will convert urea in the fertilizer back to NH3, called hydrolysis. During the hydrolysis process, N in urea fertilizer can be reduced because a part of N forms NH3 and escapes unwantedly. Therefore, it is necessary to apply appropriate management and production techniques to minimize the loss of this valuable nutrient source.

– Newly hydrolyzed urea, slightly alkaline (about less than half a pH unit) has the ability to neutralize acidity but not high in a short time, the final reaction is slightly acidic. CO2 gas produced on the ground is beneficial for the photosynthesis of plants.

Application of urea fertilizer for crops

Can urea fertilizer kill weeds?

Killing weeds with urea fertilizer seems impossible. Because urea fertilizer contains high N content, necessary for the growth of plants... and of course it is also necessary for the growth of grass. So urea fertilizer can kill weeds? Do you believe it?

Urea fertilizer - H2SO4 is mixed together according to many different formulas. It has a specific gravity of about 11.8 - 12.8 pounds/gallon, high viscosity, pH<1

Depending on the requirements of cultivation, people mix urea fertilizer - H2SO4 with different ratios. If you want to meet the nitrogen requirements of plants, use fertilizer with high urea content. If you want to improve the soil, use fertilizer with high H2SO4 content.

People use urea fertilizer - H2SO4 as a type of herbicide. This solution can kill many types of broadleaf weeds. However, it does not kill common grass and wax grass.

Urea – H2SO4 fertilizer is used by dissolving it in irrigation water for plants. If the Bicarbonate content or pH of the irrigation water is high, applying urea – H2SO4 fertilizer through the irrigation system will be very effective.

Can urea fertilizer kill weeds?

Guide to applying urea fertilizer properly

Urea fertilizer is adaptable to many different climates, can be effective on many different types of soil, for different types of crops. Urea is suitable for fertilizing on acid and alkaline soil.

Urea fertilizer is used as a top dressing. Urea provides essential nutrients for the growing process of plants. Urea fertilizer can be used as a foliar fertilizer, sprayed directly on leaves, diluted to a concentration of 0.5 - 1.5%.

Some notes when using urea fertilizer

- Urea fertilizer needs to be stored carefully in polyethylene bags, away from sunlight. Because fertilizer is very easy to decompose and evaporate when exposed to air and sunlight. When finished using, use it up immediately or tie it tightly, store in a dry place, avoid exposure to sunlight for next use.

– Excess nitrogen fertilizer will weaken plants, make them prone to falling, susceptible to pests and environmental pollution. In addition, agricultural products containing a lot of nitrate will adversely affect the health of users.

– This type of fertilizer is very volatile and easily washed away. Therefore, farmers should pay attention to fertilizing appropriately to avoid waste.

– If the amount of Biurea in the fertilizer exceeds the prescribed level, it can poison the plants. However, to overcome this, it is necessary to mix urea with powdered soil for 2 to 3 days before fertilizing, which will cause Biurea to hydrolyze and become ammonium carbonate.

– Farmers need to read the instructions carefully, ask for advice from the seller or agricultural engineers to be able to fertilize most effectively.

Urea is a volatile fertilizer

You need to use nitrogen fertilizer for your plants. You are wondering where to buy quality and reputable products. VNT is the trusted address for you. Contact us for advice on products and answers to all your questions.