The Latest Cotton Planting Techniques and Methods Tutorial
Cotton is one of the world's most important crops, with large yields and low production costs, making cotton products relatively inexpensive, and it can be made into fabrics of many specifications, from lightweight transparent voile to thick canvas and velveteen, suitable for making all kinds of clothing, furnishing fabrics and industrial fabrics, and it is also an important honey-source plant. Let's take a look at cotton planting techniques together below!
Planting Conditions
Cotton is a light-loving crop, suitable for growing under relatively sufficient light conditions, with both the light compensation point and the light saturation point being high. The physiological water requirements differ at each growth stage. From sowing to emergence, a water content of 70-80% of field capacity in the 0-20 cm soil layer is suitable; at the seedling stage, a water content of 60-70% of field capacity in the 0-40 cm soil layer is suitable; at the early budding stage, a water content of 65-75% of field capacity in the 0-60 cm soil layer is suitable; after the full budding stage, a water content of 70-80% of field capacity in the 0-80 cm soil layer is suitable; and at the boll-opening stage, keeping the soil relative water content at 55-70% is suitable. Cotton growth and development require water and nutrients, which are mainly obtained from the soil through the root system; the required temperature and air are partly taken from the soil, and at the same time mechanical support from the soil is needed for growth.
Applying Sufficient Base Fertilizer
Cotton has a long growth period, and its root system is deep and extensive, requiring not only abundant mineral nutrients in the surface soil but also relatively high fertility maintained in the deeper plow layer, with the ability to slowly release nutrients. Base fertilizer is applied to the soil by plowing before cotton sowing, which can meet this requirement. Base fertilizer is mainly farmyard manure, which can be applied to the soil in autumn and winter together with deep plowing and deep turning, or applied during land preparation in spring. Generally, apply 3000-4000 kg of high-quality farmyard manure per mu, 30-50 kg of Stanley compound fertilizer, and at the same time apply 1-2 kg each of zinc and boron fertilizer as a base application per mu.
Sowing at the Right Time
1. Time: In production, the suitable sowing period is generally when the 5 cm soil temperature is stably above 12-14°C, or when the air temperature is stably above 16°C. Sowing at the right time can make cotton plants grow steadily, promote earlier budding and flowering, extend the boll-setting time, and help achieve early maturity, high yield and good quality. Sowing too early with low soil temperature can easily cause seed rot and missing seedlings. Sowing too late delays each growth stage, leading to late maturity, reduced yield and lower fiber quality.
2. Seed quantity: The sowing quantity should be determined according to the sowing method, seed quality, retained seedling density, soil and climate conditions, etc. Too little makes it difficult to ensure the proper number of plants, affecting yield. Too much wastes cotton seed and also causes crowding of cotton seedlings, easily forming leggy seedlings and increasing the labor for thinning, etc. When the seed germination rate is low, soil moisture is poor, the soil is clayey or saline-alkali, or underground pests are severe, the sowing quantity should be increased as appropriate.
3. Depth: Cotton cotyledons are fat and large, with poor soil-piercing ability, and sowing depth is closely related to the time of emergence, the completeness of cotton seedlings, and their strength or weakness. Sowing too deep, with low temperature, makes it difficult to pierce the soil, slows emergence, consumes more nutrients, and produces thin and weak seedlings, and may even cause seed rot and bud rot resulting in missing seedlings. Sowing too shallow makes it easy to dry out, causing missing seedlings and broken rows. Sowing depth should be determined according to soil texture and moisture. In principle, the sowing depth should be controlled at 3-4 cm. For soil with good moisture and relatively clayey texture, the sowing depth should be shallow; for soil with poor moisture and relatively sandy texture, deeper sowing is appropriate.
Pruning and Topping
1. Removing leaf branches: After the first fruiting branch appears, promptly remove the leaf branches below the first fruiting branch, while retaining the main stem leaves to provide organic nutrients to the root system; this is called removing leaf branches or wiping off oil shoots. Removing leaf branches is one of the means of controlling excessive cotton growth to obtain high yield. Cotton plants in weak seedling areas and missing-seedling spots may not have their leaf branches removed, and after they elongate, the side tips can be pinched. Removing leaf branches is carried out in the early budding stage. Generally, medium-maturing varieties with a loose plant type need leaf branch removal, while early-maturing varieties with a compact plant type may not need this work.
2. Topping the central bud: Topping can eliminate apical dominance, regulate the balanced distribution of photosynthetic products among organs, increase the proportion of nutrients distributed to the lower fruiting organs, strengthen the transport of assimilates to the root system, enhance root vitality and nutrient absorption capacity, and thereby increase the boll-setting rate.
3. Pinching side tips: Pinching side tips means removing the top tips of fruiting branches, which can control the lateral growth of fruiting branches, improve field ventilation and light transmission conditions, help increase the boll-setting rate, increase boll weight, and promote early maturity. In production, for cotton fields with sufficient fertilizer and water, relatively vigorous growth, and relatively high density, during the middle and late stages of field management, remove the group tips in stages from bottom to top, and in combination with boll setting, retain 2-3 fruiting nodes on the lower part, 3-4 fruiting nodes on the middle part, and for the upper part, pinch according to the timing of the local first frost.
Reasonable Topdressing
1. Light application of seedling fertilizer: Topdressing seedling fertilizer can promote root development and cultivate strong seedlings. Seedling fertilizer is generally mainly nitrogen fertilizer and can be determined according to seedling condition, soil fertility, base fertilizer, etc. For cotton fields with poor soil fertility, insufficient base fertilizer, and weak growth, apply 5-10 kg of urea or high-nitrogen compound fertilizer per mu, by furrow band application, and cover with soil after application. For cotton fields with high fertility and sufficient base fertilizer, seedling fertilizer may not be applied.
2. Steady application of bud fertilizer: After cotton budding, the demand for nutrients gradually increases. Reasonable topdressing at the bud stage can meet the needs of cotton plant growth, coordinate the relationship between vegetative growth and reproductive growth, and promote steady plant growth. Generally, in the early budding stage of cotton, apply 15-20 kg of Stanley compound fertilizer per mu. The topdressing method is preferably deep furrow application, and keep an appropriate distance from the cotton plants to avoid root damage and affect normal growth.
3. Applying flower and boll fertilizer: The flower and boll stage is the period when cotton needs the most fertilizer. Heavy application of flower and boll fertilizer has a significant effect on striving for the “three bolls”. Generally, apply 20-30 kg of urea and Stanley compound fertilizer per mu. For cotton fields with poor soil fertility, little base fertilizer, and weak growth, it may be applied appropriately earlier, when more than 80% of cotton plants have flowered and 1-2 young bolls have set, and the topdressing method is preferably band application.
4. Applying top-covering fertilizer: Supplemental application of top-covering fertilizer mainly prevents cotton from lacking fertilizer in the later stage and premature senescence, promotes steady plant growth, enhances disease resistance, insect resistance and premature senescence resistance, and strives to set more autumn bolls and increase boll weight. Generally, foliar topdressing is carried out before and after topping. For cotton fields lacking nitrogen or showing premature senescence, spray 50-75 kg of 1% urea solution per mu, once every 5-7 days, for 2-3 consecutive sprays. For cotton fields lacking phosphorus or potassium or with excessive growth, delayed greenness and late maturity, spray 0.2% potassium dihydrogen phosphate solution once every 7-10 days, for 2-3 consecutive sprays, so as to achieve the goals of no yellowing leaves, no leaf drop, no premature senescence in the later stage, and high yield and good quality.