Using potassium fertilizer for rice

(Baonghean) -There are two types of potassium fertilizers currently sold on the market. One is potassium chloride (KCl), which is light brick red in color. This type of potassium fertilizer contains 55-60% pure potassium (K2O). Another type is potassium sulfate (K2SO4), which is white in color, and contains 50-55% pure potassium (K2O).

Currently, the time when rice is standing and preparing to form panicles, farmers are in dire need of potassium fertilizer, but it is also the time when some fertilizer businesses are offering and selling products at surprisingly low prices to trick farmers into buying fake fertilizer, losing money and harming property.

Usually, fake and counterfeit potash fertilizers are produced by mixing cheap ammonium sulfate with about 8-10% real potash fertilizer and adding finely ground brick powder to increase the weight of the fertilizer. There are also types of potash fertilizers produced in the form of imported compound fertilizers, including 80% ammonium sulfate, mixed with 20% potassium chloride and sold at 11,000-12,000 VND/kg, approximately the price of real potash fertilizers. In addition, there are some businesses that smuggle potash fertilizers from China through unofficial channels, the pure potash content is only 20-25%, the rest is dyed to look like real potash.

So how to distinguish real and fake potassium fertilizer.

Real good quality potassium fertilizer has a uniform color, is dry, does not stick to the hand, is still clean, dissolves quickly in water, does not float, and does not leave residue at the bottom of the bowl or cup of water when the fertilizer is mixed in. Fake potassium fertilizer has the opposite of the above phenomena.

Using potassium fertilizer for rice is best done in 2 stages: the first time, top dressing after 12-15 days of planting rice, depending on the long-term or short-term rice variety. At this time, it is necessary to apply an average of 2-3 kg per sao (500 m2) for the rice plant to grow strong, be hard to plant, and have effective tillers. The second fertilization is very important when the rice plant is standing, preparing to form panicles. This fertilization will increase the number of grains per panicle, reduce the rate of empty grains, increase weight, grain, improve the quality of the rice to make it more delicious and increase the ability to resist lodging when strong winds appear. The amount of potassium fertilizer needed at this time is 4.5 kg per sao for hybrid rice and 3-4 kg per sao for purebred rice varieties.

To be assured of not buying fake potassium fertilizer, farmers should go to fertilizer stores of reputable, branded fertilizer companies to buy.

Doan Tri Tue