A Detailed Guide to Nitrogen Fertilizer Application Timing, Per-Mu Dosage and Fertilization Techniques for Corn

Corn is also known as maize, bangzi, baogu, baomi, baosu, yujiao, baomi, zhenzhumi, baolu, daluosu, and is called zhenzhuli in the Liaoning dialect of Northeast China. It is the crop with the highest total production in the world. So do you know when to apply nitrogen fertilizer to it? How much should be applied per mu? What are the fertilization techniques? Now let's take a look together with the editor.

When should nitrogen fertilizer be applied to corn?

1. In the stage dominated by vegetative growth, generally early-maturing varieties have 5-6 leaves unfolded, mid-maturing varieties have 7 leaves unfolded, and the tassel growth cone begins to elongate. This is one of the best fertilization periods for corn, and the fertilization amount accounts for about 30% of the total fertilization amount. At this time, sufficient fertilizer and water are the key to promoting strong seedlings to emerge early, grow steadily, and build a high-yield framework. Apply nitrogen fertilizer 2/10.

2. In the stage where vegetative growth and reproductive growth proceed together, the 11th leaf of corn has unfolded, the plant has formed about 60%, and the tassel has begun floret differentiation. This is the key period for the formation of the number of kernels per ear. Apply nitrogen fertilizer 5/10.

3. After corn pollination, the stalk basically stops growing and has entered the stage dominated by reproductive growth. At this time, for corn with insufficient fertilizer supply or signs of fertilizer deficiency after tasseling, a grain-promoting fertilizer should be applied once. This is especially important for medium-yield fields and late-maturing varieties. Apply nitrogen fertilizer 1/10.

How much should be applied per mu of corn?

Fertilizer application rate = (the amount of a certain element required for the planned yield - the amount of that element supplied by the soil) / (the content of that element in the fertilizer (%) × the seasonal utilization rate of the fertilizer (%)).

The utilization rate of fertilizer varies greatly. According to experiments, the seasonal utilization rate of organic farmyard manure is usually about 30%, that of nitrogen chemical fertilizer is about 40%-50% (calculated at 40%), and that of phosphorus and potassium chemical fertilizers is about 30%-40% (calculated at 30%). That is to say, the required amount of nitrogen fertilizer (urea) is 32.16 (kg/mu).

What are the fertilization techniques for corn?

1. Prevent premature aging. In rainy areas, drainage and waterlogging prevention should be done well. If there is a trend of premature aging or the leaves turn yellow, refined fertilizer should be applied or phosphate fertilizer sprayed at the early flowering stage to extend the green leaves and increase the ear. Applying plant ash or potassium sulfate fertilizer more at the seedling stage can also prevent premature aging.

2. Prevent empty stalks. Insufficient mineral supply, nutritional imbalance, failure to meet the nutrient requirements during the ear differentiation stage, or excessive density, weak photosynthesis, and too much nitrogen fertilizer, too little phosphorus, and potassium deficiency can all cause empty stalks. When planting, attention should be paid to density. It is required that large-row corn does not close the rows, so as to ensure ventilation and air permeability between plants and rows, and supply nutrients and water timely and appropriately to facilitate ear differentiation and development. At the same time, attention should be paid to the proper combination of the three elements nitrogen, phosphorus, and potassium during fertilization.

3. Prevent missing kernels and bald tips. To prevent premature aging of plants, the key is to prevent damage from diseases and pests, and apply more phosphate fertilizer and potassium fertilizer. If drought occurs during silking, timely watering and irrigation should be carried out, and artificial pollination is best carried out during the flowering stage.

4. Prevent lodging. If the retained seedling density is too high, improper fertilizer and water management during stalk elongation can easily cause lodging and affect yield. When planting, the tillage layer should be deepened, base fertilizer should be increased, and soil should be properly banked during intertillage so that corn can take root firmly. When fertilizing, attention should be paid to the combination of nitrogen, phosphorus, and potassium, and attention should be paid to plant density to ensure that the leaves have enough sunlight during the growth period, making the plants sturdy and the seedlings sturdy, so as to increase lodging resistance.