What fertilizer is best for cotton? A detailed guide to high-yield fertilization techniques

With advances in cotton planting methods and techniques, fertilization methods also need to be adjusted appropriately. So how should cotton be fertilized to achieve high yield? What fertilizer is generally best to use? How should fertilization be done?

What fertilizer is generally best for cotton

Normal growth and development of cotton requires nitrogen, phosphorus, potassium, iron, zinc, copper, manganese and various other elements. According to research data, for every 100kg of lint cotton formed, cotton absorbs approximately 1336kg of pure nitrogen, 4.65kg of phosphorus pentoxide, and 13.35kg of potassium oxide. Fertilizer requirements increase as yield levels rise. There are slight differences among different varieties and yield levels. During the seedling stage, cotton absorbs 5% nitrogen, 3% available phosphorus, and 3% available potassium; from the squaring stage to the early flowering stage, it absorbs 11% nitrogen, 7% available phosphorus, and 9% available potassium; from the early flowering stage to the full flowering stage, it absorbs 56% nitrogen, 24% available phosphorus, and 36% available potassium; from the full flowering stage to the boll stage, it absorbs 23% nitrogen, 52% available phosphorus, and 42% available potassium; after boll opening, it absorbs 5% nitrogen, 14% available phosphorus, and 10% available potassium. From this it can be seen that the peak fertilizer absorption period for cotton is during the flowering and boll stage, with the nitrogen absorption peak during the full flowering stage and the phosphorus and potassium absorption peak from the full flowering stage to the boll opening stage. Elements such as zinc, boron and manganese should be applied according to soil nutrient supply conditions, supplementing deficiencies in a targeted manner. Cotton requires relatively high soil fertility in the cotton field, so sufficient basal fertilizer must be applied, along with timely and appropriate topdressing. Generally, the principle of light early and heavy late application is followed, applying according to local conditions, timing and seedling growth.

Cotton fertilization methods:

1. Light, partial or no seedling fertilizer: When cotton enters the vigorous growth stage, nutrient competition among plants becomes intense, and weak seedlings may fail to square or flower. When basal fertilizer is sufficient and seedlings emerge uniformly, spraying New High-Lipid Film to protect existing nutrients from loss allows for light or no seedling fertilizer application; when seedling height, vigor and strength are uneven, apply additional fertilizer to short and weak seedlings, then spray photosynthetic nutrient film fertilizer, which helps plants absorb large amounts of light fertilizer, light energy and light, is compatible with conventional fertilizers, and supplies nutrients to support plant growth and development to the maximum.

2. Steady application of squaring fertilizer: After cotton squares, fruiting branches begin to appear and fertilizer requirements increase rapidly. Nitrogen fertilizer should be appropriately topdressed, along with spraying cotton boll-strengthening agent to supplement nutrient deficiencies, enabling the cotton plant's growth function to transform toward reproductive function, thereby increasing the boll-setting rate of cotton squares.

3. Supplementary application of topping fertilizer: Apply an appropriate amount of topping fertilizer. Combined with pest control, foliar application of Flower-Promoting King No. 3 cotton topping agent can force nutrients from the top of the cotton plant to flow back to boll development, weakening apical dominance until the growing tip stops growing. This achieves the purpose of topping. Using it together with mepiquat chloride can effectively improve the canopy ventilation of the cotton field population, prevent premature aging, increase effective boll weight, raise yield, and save costs while increasing efficiency.

The above are the cotton fertilization methods introduced by the editor. We hope the editor's summary can help everyone better grow cotton. If you want to learn more, please follow our WeChat account, Huobao Agricultural Chemical Investment Network (WeChat ID: nh1988TV), where more agricultural knowledge and planting encyclopedias are presented for you.

How to fertilize cotton for high yield

In recent years, the large-scale introduction of insect-resistant cotton in various regions has effectively controlled cotton bollworm damage, greatly reduced the number of square and boll shedding, promoted vigorous reproductive growth with early and abundant boll setting, and caused the fertilizer requirement peak to arrive quickly and intensely. If fertilized according to traditional methods, it often cannot meet these demands, resulting in poor vegetative growth and premature aging. In addition, because insect-resistant cotton has been introduced with insect-resistance genes, its disease resistance has declined, making it prone to red leaf disease, stem blight and other diseases.

Increase potassium fertilizer, reduce nitrogen and phosphorus fertilizer

Potassium fertilizer has the function of enhancing cotton's stress resistance and disease prevention effects, so insect-resistant cotton needs increased potassium fertilizer. If nitrogen and phosphorus fertilizers are blindly increased while ignoring organic fertilizer and potassium fertilizer application, it will not only increase fertilization costs but also lead to premature aging or late maturity of cotton, greatly affecting yield and quality.

The procedure for increasing organic fertilizer and potassium fertilizer while reducing nitrogen and phosphorus fertilizer is as follows: apply about 3000 kg of organic fertilizer and 10-15 kg of potassium fertilizer per mu. Reduce from the traditional 25-30 kg of urea and 50 kg of superphosphate per mu to 12 kg of urea and 25 kg of superphosphate per mu. Apply the above fertilizers together with land preparation at a depth of more than 15 cm.

What principles apply to cotton fertilization

Change flowering and boll fertilizer from one concentrated application to two split applications

The flowering and boll stage is the period of most vigorous growth and development and highest fertilizer demand in cotton's entire life cycle, requiring heavy application of flowering and boll fertilizer. Generally, 25-30 kg of urea and 10 kg of potassium fertilizer per mu are needed. In view of the characteristic of insect-resistant cotton flowering and setting bolls quickly and in a concentrated manner, 2/3 of the flowering and boll fertilizer can be applied at the early flowering stage, with the remaining 1/3 topdressed about 15 days later. This can both meet the needs of continuous flowering and boll setting in cotton and effectively avoid excessive vegetative growth and premature aging of the cotton plant.

Change topping fertilizer from soil topdressing to foliar topdressing

In the late growth stage of cotton, the root absorption capacity declines. If nutrients are insufficient, premature aging is easily triggered, requiring topping fertilizer. Foliar topdressing of topping fertilizer has the advantages of being simple, quick-acting, effective and fertilizer-saving, and can save 2/3 of the fertilizer compared with soil topdressing.

The above is an introduction to some cotton fertilization techniques. Cotton growers can refer to the above methods and combine them with actual planting conditions to carry out reasonable fertilization.