What fertilizer is good for corn in the later stage

It is recommended to choose high potassium compound fertilizer or urea combined with potassium dihydrogen phosphate for topdressing in the later stage of corn growth. Corn has a high demand for potassium from heading to grain filling stage, and reasonable fertilization can help improve grain plumpness and yield.

1. High potassium compound fertilizer

High potassium compound fertilizer contains balanced nitrogen, phosphorus, and potassium elements, making it particularly suitable for use during the corn filling period. Potassium can promote the transfer of photosynthetic products to grains and enhance plant lodging resistance. Choose a compound fertilizer with a nitrogen phosphorus potassium ratio of 15-5-25 or similar, and apply it around the roots of the plant before rain or after irrigation to avoid direct contact with stems and leaves. Proper soil cultivation after fertilization can reduce nutrient loss.

2. Urea combined with potassium dihydrogen phosphate

Urea can quickly supplement nitrogen elements to prevent premature leaf senescence, while potassium dihydrogen phosphate provides phosphorus and potassium nutrition. Mix urea with potassium dihydrogen phosphate in a ratio of 2:1, dilute with water, and spray on the leaves every 7-10 days. This method can avoid soil fixation, especially suitable for arid areas or aging plants with reduced root absorption capacity. Spraying in the evening can reduce evaporation losses.

3. Humic acid water-soluble fertilizer

Humic acid containing water-soluble fertilizer can improve the soil microenvironment and promote the absorption and utilization of nutrients by corn. After chelation with trace elements, humic acid can be precisely applied to the root zone through drip irrigation systems. This type of fertilizer can alleviate soil compaction problems and is particularly suitable for continuous planting in farmland. When using, the concentration should be controlled at around 0.2%, as excessive concentration may inhibit growth.

4. Biological fertilizer

Biological fertilizer containing phosphorus and potassium solubilizing bacteria can activate fixed nutrients in soil. Combining a small amount of fertilizer during the corn milk ripening period can improve fertilizer utilization efficiency. Choose strains such as Bacillus subtilis and Bacillus coagulans to avoid using them together with fungicides. Biological microbial fertilizers need to keep the soil moist in order to achieve optimal results.

5. Plant ash

Plant ash is a natural source of potassium fertilizer, rich in potassium carbonate and trace elements. Spraying 100-150 kilograms per acre during the corn wax ripening period can supplement potassium and regulate soil pH. Before use, it is necessary to sieve thoroughly to avoid burning the plants with unburned carbon particles. Saline alkali land should be used with caution to prevent exacerbating soil salinization.

In the later stage of corn fertilization, the formula should be adjusted according to soil testing results. For sandy soil, a small amount should be applied multiple times, and for clay soil, the amount can be appropriately increased. Timely irrigation after topdressing can improve fertilizer efficiency, but it is necessary to avoid water accumulation that can cause root hypoxia. At the same time, pay attention to the growth of the plants, and supplement trace elements with foliar fertilizer when symptoms of nutrient deficiency occur. Reasonable crop rotation and straw returning can improve soil fertility and reduce dependence on chemical fertilizers. Fertilization should be stopped 20 days before harvest to ensure the quality and safety of agricultural products.